Pub Date : 2025-01-01DOI: 10.1016/j.mtphys.2024.101638
Wenjiang Zhou , Nianjie Liang , Xiguang Wu , Shiyun Xiong , Zheyong Fan , Bai Song
Machine-learned potentials (MLPs) have been extensively used to obtain the lattice thermal conductivity (κ) via atomistic simulations. However, the impact of force errors in various MLPs on thermal transport has not been widely recognized and remains to be fully understood. Here, we employ MLP-driven molecular dynamics (MD) and anharmonic lattice dynamics (LD) to systematically investigate how the calculated κ varies with the force errors, using boron arsenide as a prototypical material to emphasize the challenges associated with high thermal conductivity. We consistently observe an underestimation of κ in MD simulations with different MLPs including the neuroevolution potential, deep potential, and moment tensor potential (MTP). We propose a robust second-order extrapolation scheme based on controlled force noises via the Langevin thermostat to correct this underestimation. The corrected results achieve a good agreement with previous experimental measurements from 200 K to 600 K. In contrast, the κ values from LD calculations with MLPs readily align with the experimental data, which is attributed to the much smaller effects of the force errors on the force-constant calculations. Our findings provide deeper physical insight into the effect of the force errors in machine-learned potentials on thermal transport, and are particularly instrumental for simulating and seeking high-κ materials. In addition, we also make our modified version of the MLIP package publicly accessible in order to facilitate the accurate calculation of heat current in MTP-based MD simulations.
{"title":"Insight into the effect of force error on the thermal conductivity from machine-learned potentials","authors":"Wenjiang Zhou , Nianjie Liang , Xiguang Wu , Shiyun Xiong , Zheyong Fan , Bai Song","doi":"10.1016/j.mtphys.2024.101638","DOIUrl":"10.1016/j.mtphys.2024.101638","url":null,"abstract":"<div><div>Machine-learned potentials (MLPs) have been extensively used to obtain the lattice thermal conductivity (<em>κ</em>) via atomistic simulations. However, the impact of force errors in various MLPs on thermal transport has not been widely recognized and remains to be fully understood. Here, we employ MLP-driven molecular dynamics (MD) and anharmonic lattice dynamics (LD) to systematically investigate how the calculated <em>κ</em> varies with the force errors, using boron arsenide as a prototypical material to emphasize the challenges associated with high thermal conductivity. We consistently observe an underestimation of <em>κ</em> in MD simulations with different MLPs including the neuroevolution potential, deep potential, and moment tensor potential (MTP). We propose a robust second-order extrapolation scheme based on controlled force noises via the Langevin thermostat to correct this underestimation. The corrected results achieve a good agreement with previous experimental measurements from 200 K to 600 K. In contrast, the <em>κ</em> values from LD calculations with MLPs readily align with the experimental data, which is attributed to the much smaller effects of the force errors on the force-constant calculations. Our findings provide deeper physical insight into the effect of the force errors in machine-learned potentials on thermal transport, and are particularly instrumental for simulating and seeking high-<em>κ</em> materials. In addition, we also make our modified version of the MLIP package publicly accessible in order to facilitate the accurate calculation of heat current in MTP-based MD simulations.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"50 ","pages":"Article 101638"},"PeriodicalIF":10.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142886809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.mtphys.2024.101639
Wenjing Wei , Yang Hong , Xiaolei Shi , Yang Li , Kai Cui , Tianyu Zhang , Xin Jia , Jingyang Li , Hongjun Kang , Wei Qin , Xiaohong Wu
The limited irradiation stability of metal-oxide-semiconductor field-effect transistor (MOSFET) devices has restricted their application in deep space exploration missions. Therefore, it is an urgent need to develop a new and efficient packaging hardening techniques to improve the irradiation stability of MOSFET devices. Herein, Cr0.5NbMoTaW was prepared by localized high-energy mechanical alloying and coated on the MOSFET's surface, and the packaged MOSFETs exhibit excellent irradiation stability. The threshold voltage change value of Cr0.5NbMoTaW packaged MOSFET device (0.26 V) is lower than the unpackaged MOSFET (4.15 V) after high-energy electron irradiation. Experimental and theoretical calculations show that Cr induces lattice shrinkage of Cr0.5NbMoTaW high-entropy alloys, leading to an improved density of nucleus. This increases the probability of elastic and inelastic collision between high-energy electrons and the nucleus, thus achieving excellent irradiation stability of packaged MOSFET devices. This work presents a strategy to improve the irradiation stability of MOSFET devices by using high-entropy alloy packaging.
{"title":"Enhanced irradiation stability of MOSFET devices realized by improving nucleus density of CrxNbMoTaW generated by lattice shrinkage","authors":"Wenjing Wei , Yang Hong , Xiaolei Shi , Yang Li , Kai Cui , Tianyu Zhang , Xin Jia , Jingyang Li , Hongjun Kang , Wei Qin , Xiaohong Wu","doi":"10.1016/j.mtphys.2024.101639","DOIUrl":"10.1016/j.mtphys.2024.101639","url":null,"abstract":"<div><div>The limited irradiation stability of metal-oxide-semiconductor field-effect transistor (MOSFET) devices has restricted their application in deep space exploration missions. Therefore, it is an urgent need to develop a new and efficient packaging hardening techniques to improve the irradiation stability of MOSFET devices. Herein, Cr<sub>0.5</sub>NbMoTaW was prepared by localized high-energy mechanical alloying and coated on the MOSFET's surface, and the packaged MOSFETs exhibit excellent irradiation stability. The threshold voltage change value of Cr<sub>0.5</sub>NbMoTaW packaged MOSFET device (0.26 V) is lower than the unpackaged MOSFET (4.15 V) after high-energy electron irradiation. Experimental and theoretical calculations show that Cr induces lattice shrinkage of Cr<sub>0.5</sub>NbMoTaW high-entropy alloys, leading to an improved density of nucleus. This increases the probability of elastic and inelastic collision between high-energy electrons and the nucleus, thus achieving excellent irradiation stability of packaged MOSFET devices. This work presents a strategy to improve the irradiation stability of MOSFET devices by using high-entropy alloy packaging.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"50 ","pages":"Article 101639"},"PeriodicalIF":10.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142886810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01DOI: 10.1016/j.mtphys.2024.101613
Jing Wang , Feng Xiang , Yangyang Song , Haixia Wang , Chen Chen , Xian Zhao , Weiliu Fan
<div><div>Understanding the relationship between the structure, activity, and selectivity of dual-atom catalysts (DACs) in electrocatalytic CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR) remains challenging because of the diverse bimetallic combinations and their complex electronic interactions. Herein, we integrated high-throughput screening and density functional theory to explore the catalytic performance of 66 M<sub>I</sub>M<sub>II</sub>-PC<sub>6</sub> (M<sub>I</sub>M<sub>II</sub> = pairs of V-Cu, Ru, Rh, Os, Ir) for the CO<sub>2</sub>RR to C1 and C2. The results indicate that the synergistic effect between bimetals can effectively regulate the adsorption strengths of key intermediates such as ∗CO, ∗OCH<sub>2</sub>CH<sub>2</sub>, and C-C coupling process. Besides, the C<sub>2</sub>H<sub>4</sub> or C<sub>2</sub>H<sub>5</sub>OH selectivity of the screened DACs is determined by the dominant intermediate (∗O or ∗OCH<sub>2</sub>CH<sub>2</sub>) generated by the protonation of ∗OCH<sub>2</sub>CH. DAC with a smaller ΔG<sub>∗O</sub> relative to <span><math><mrow><msub><mrow><mo>Δ</mo><mi>G</mi></mrow><mrow><msub><mrow><mo>∗</mo><mtext>OCH</mtext></mrow><mn>2</mn></msub><msub><mtext>CH</mtext><mn>2</mn></msub></mrow></msub></mrow></math></span> favors C<sub>2</sub>H<sub>4</sub> formation, while a larger ΔG<sub>∗O</sub> indicates a preference for C<sub>2</sub>H<sub>5</sub>OH. Through a four-step rapid screening strategy, CrCu, CrRu, CrRh, and CuRu-PC<sub>6</sub> were identified as potential DACs for CH<sub>4</sub> production. Furthermore, CrFe, MnOs, and MnRu-PC<sub>6</sub> showed potential for C<sub>2</sub>H<sub>4</sub> generation, while MnRh, MnIr, CoRh, and CoIr-PC<sub>6</sub> displayed outstanding catalytic performance in generating C<sub>2</sub>H<sub>5</sub>OH. Notably, the intrinsic descriptors <span><math><mrow><msub><mi>φ</mi><mrow><mi>C</mi><msub><mi>H</mi><mn>4</mn></msub></mrow></msub><mo>=</mo><mrow><mo>(</mo><mrow><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mo>+</mo><mfrac><mn>1</mn><mn>2</mn></mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mtext>II</mtext></msub></msub></mrow><mo>)</mo></mrow><mo>∗</mo><msub><mi>X</mi><msub><mi>M</mi><mi>I</mi></msub></msub></mrow></math></span>, <span><math><mrow><msub><mi>φ</mi><mrow><mi>C</mi><mn>2</mn></mrow></msub><mo>=</mo><mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mrow><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mtext>II</mtext></msub></msub><mo>∗</mo><mrow><mo>(</mo><mrow><mn>2</mn><msub><mi>R</mi><msub><mi>M</mi><mi>I</mi></msub></msub><mo>+</mo><msub><mi>R</mi><msub><mi>M</mi><mtext>II</mtext></msub></msub></mrow><mo>)</mo></mrow></mrow></mfrac></mrow></math></span>, and <span><math><mrow><msub><mi>φ</mi><mtext>selec</mtext></msub><mo>=</mo><mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mrow><mrow><mo>(</mo><msub><mrow><msub><mrow><mi>N</mi><mi>d
{"title":"High-throughput screening of MIMII-PC6 dual-atom electrocatalysts for efficient and selective electrocatalytic reduction of CO2 to C1 and C2 products","authors":"Jing Wang , Feng Xiang , Yangyang Song , Haixia Wang , Chen Chen , Xian Zhao , Weiliu Fan","doi":"10.1016/j.mtphys.2024.101613","DOIUrl":"10.1016/j.mtphys.2024.101613","url":null,"abstract":"<div><div>Understanding the relationship between the structure, activity, and selectivity of dual-atom catalysts (DACs) in electrocatalytic CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR) remains challenging because of the diverse bimetallic combinations and their complex electronic interactions. Herein, we integrated high-throughput screening and density functional theory to explore the catalytic performance of 66 M<sub>I</sub>M<sub>II</sub>-PC<sub>6</sub> (M<sub>I</sub>M<sub>II</sub> = pairs of V-Cu, Ru, Rh, Os, Ir) for the CO<sub>2</sub>RR to C1 and C2. The results indicate that the synergistic effect between bimetals can effectively regulate the adsorption strengths of key intermediates such as ∗CO, ∗OCH<sub>2</sub>CH<sub>2</sub>, and C-C coupling process. Besides, the C<sub>2</sub>H<sub>4</sub> or C<sub>2</sub>H<sub>5</sub>OH selectivity of the screened DACs is determined by the dominant intermediate (∗O or ∗OCH<sub>2</sub>CH<sub>2</sub>) generated by the protonation of ∗OCH<sub>2</sub>CH. DAC with a smaller ΔG<sub>∗O</sub> relative to <span><math><mrow><msub><mrow><mo>Δ</mo><mi>G</mi></mrow><mrow><msub><mrow><mo>∗</mo><mtext>OCH</mtext></mrow><mn>2</mn></msub><msub><mtext>CH</mtext><mn>2</mn></msub></mrow></msub></mrow></math></span> favors C<sub>2</sub>H<sub>4</sub> formation, while a larger ΔG<sub>∗O</sub> indicates a preference for C<sub>2</sub>H<sub>5</sub>OH. Through a four-step rapid screening strategy, CrCu, CrRu, CrRh, and CuRu-PC<sub>6</sub> were identified as potential DACs for CH<sub>4</sub> production. Furthermore, CrFe, MnOs, and MnRu-PC<sub>6</sub> showed potential for C<sub>2</sub>H<sub>4</sub> generation, while MnRh, MnIr, CoRh, and CoIr-PC<sub>6</sub> displayed outstanding catalytic performance in generating C<sub>2</sub>H<sub>5</sub>OH. Notably, the intrinsic descriptors <span><math><mrow><msub><mi>φ</mi><mrow><mi>C</mi><msub><mi>H</mi><mn>4</mn></msub></mrow></msub><mo>=</mo><mrow><mo>(</mo><mrow><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mo>+</mo><mfrac><mn>1</mn><mn>2</mn></mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mtext>II</mtext></msub></msub></mrow><mo>)</mo></mrow><mo>∗</mo><msub><mi>X</mi><msub><mi>M</mi><mi>I</mi></msub></msub></mrow></math></span>, <span><math><mrow><msub><mi>φ</mi><mrow><mi>C</mi><mn>2</mn></mrow></msub><mo>=</mo><mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mrow><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mtext>II</mtext></msub></msub><mo>∗</mo><mrow><mo>(</mo><mrow><mn>2</mn><msub><mi>R</mi><msub><mi>M</mi><mi>I</mi></msub></msub><mo>+</mo><msub><mi>R</mi><msub><mi>M</mi><mtext>II</mtext></msub></msub></mrow><mo>)</mo></mrow></mrow></mfrac></mrow></math></span>, and <span><math><mrow><msub><mi>φ</mi><mtext>selec</mtext></msub><mo>=</mo><mfrac><msub><mrow><mi>N</mi><mi>d</mi></mrow><msub><mi>M</mi><mi>I</mi></msub></msub><mrow><mrow><mo>(</mo><msub><mrow><msub><mrow><mi>N</mi><mi>d","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"50 ","pages":"Article 101613"},"PeriodicalIF":10.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142797525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-25DOI: 10.1016/j.mtphys.2024.101606
Jie Zhang , Changjiang Li , Chengping Lv , Haocheng Yu , Wenjun Ma , Mengyong Lei , Xiaoming Chen , Ming Liu , Xiaohui Zhang
Developing the inorganic piezoelectric particles/polymer matrix composites is a simple, effective, and low-cost strategy to manufacture the flexible, wearable sensors. But their application has been hindered by an obvious trade-off between electronic performances and mechanical deformability, because of the issue of dispersion difficulty and isolated distribution of inorganic nanofillers in matrix. Here, an ultra-soft, substrate-free, wearable piezoelectric sensor with aligned barium titanate (BTO) nanoparticles was designed and fabricated. To resolve the issue of degradation of flexibility of composites, a chemical etching treatment was introduced into the process of hydrothermal, which increased the content of tetragonal BTO nanoparticles and optimized the interaction between inorganic layer and polymer matrix. Thus, a higher sensitivity of 73.5 V/MPa was obtained by the as-prepared composites with the orientation of BTO than those of the reported BTO-based composites. Notably, the sensor with the thin functional layer demonstrated excellent stability even after 200 double-folded fatigue cycles. For this reason, the designed sensor could completely wrap or attach onto the different complex surface to simultaneously detect various dynamic signals involving the fluidic flowing, pulse rate and moved direction of body. Moreover, the foldable piezoelectric sensing array was easily fabricated by the proposed method, which offers the huge opportunity for the widespread applications in health monitoring, personal safety, and activity monitoring on the complex surface.
{"title":"Ultra-soft, foldable, wearable piezoelectric sensor based on the aligned BaTiO3 nanoparticles","authors":"Jie Zhang , Changjiang Li , Chengping Lv , Haocheng Yu , Wenjun Ma , Mengyong Lei , Xiaoming Chen , Ming Liu , Xiaohui Zhang","doi":"10.1016/j.mtphys.2024.101606","DOIUrl":"10.1016/j.mtphys.2024.101606","url":null,"abstract":"<div><div>Developing the inorganic piezoelectric particles/polymer matrix composites is a simple, effective, and low-cost strategy to manufacture the flexible, wearable sensors. But their application has been hindered by an obvious trade-off between electronic performances and mechanical deformability, because of the issue of dispersion difficulty and isolated distribution of inorganic nanofillers in matrix. Here, an ultra-soft, substrate-free, wearable piezoelectric sensor with aligned barium titanate (BTO) nanoparticles was designed and fabricated. To resolve the issue of degradation of flexibility of composites, a chemical etching treatment was introduced into the process of hydrothermal, which increased the content of tetragonal BTO nanoparticles and optimized the interaction between inorganic layer and polymer matrix. Thus, a higher sensitivity of 73.5 V/MPa was obtained by the as-prepared composites with the orientation of BTO than those of the reported BTO-based composites. Notably, the sensor with the thin functional layer demonstrated excellent stability even after 200 double-folded fatigue cycles. For this reason, the designed sensor could completely wrap or attach onto the different complex surface to simultaneously detect various dynamic signals involving the fluidic flowing, pulse rate and moved direction of body. Moreover, the foldable piezoelectric sensing array was easily fabricated by the proposed method, which offers the huge opportunity for the widespread applications in health monitoring, personal safety, and activity monitoring on the complex surface.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"50 ","pages":"Article 101606"},"PeriodicalIF":10.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142696878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-21DOI: 10.1016/j.mtphys.2024.101604
Suhao Yao , Yifan Yao , Maolin Zhang , Xueqiang Ji , Shan Li , Weihua Tang
Mist chemical vapor deposition (mist CVD) technology originated from early metal organic chemical vapor deposition (MOCVD) techniques. By mist CVD, High-quality oxide films are deposited by ultrasonic atomization of low-concentration precursor solutions under atmospheric pressure and relatively low temperature conditions. Mist CVD was first reported in 1990, and in 2008, Shinohara et al. applied mist CVD to the growth of gallium oxide (Ga2O3) epitaxial films. As an ultrawide bandgap (UWBG) semiconductor, Ga2O3 has tremendous potential in power systems and optoelectronic devices, attracting significant attention and becoming a research hotspot in recent years. Various techniques have been explored for growing Ga2O3 films. Among them, mist CVD is noted for its relatively cheap equipment, simpler operation, and competitive cost advantages, making it a promising method for Ga2O3 film growth. Using mist CVD, five crystal phases (α, β, γ, ε, and δ) of Ga2O3 films have been successfully produced, and the properties of Ga2O3 films can be easily tuned through doping and alloy engineering. Additionally, semiconductor devices have been fabricated using Ga2O3 films grown by mist CVD. However, challenges remain in terms of doping uniformity, crystal phase purity, and stability. This paper reviews the advancements in mist CVD for the deposition of Ga2O3, covering mist CVD equipment design, Ga2O3 crystal phase control, doping and alloy modulation, and device fabrication.
{"title":"Mist CVD technology for gallium oxide deposition: A review","authors":"Suhao Yao , Yifan Yao , Maolin Zhang , Xueqiang Ji , Shan Li , Weihua Tang","doi":"10.1016/j.mtphys.2024.101604","DOIUrl":"10.1016/j.mtphys.2024.101604","url":null,"abstract":"<div><div>Mist chemical vapor deposition (mist CVD) technology originated from early metal organic chemical vapor deposition (MOCVD) techniques. By mist CVD, High-quality oxide films are deposited by ultrasonic atomization of low-concentration precursor solutions under atmospheric pressure and relatively low temperature conditions. Mist CVD was first reported in 1990, and in 2008, Shinohara et al. applied mist CVD to the growth of gallium oxide (Ga<sub>2</sub>O<sub>3</sub>) epitaxial films. As an ultrawide bandgap (UWBG) semiconductor, Ga<sub>2</sub>O<sub>3</sub> has tremendous potential in power systems and optoelectronic devices, attracting significant attention and becoming a research hotspot in recent years. Various techniques have been explored for growing Ga<sub>2</sub>O<sub>3</sub> films. Among them, mist CVD is noted for its relatively cheap equipment, simpler operation, and competitive cost advantages, making it a promising method for Ga<sub>2</sub>O<sub>3</sub> film growth. Using mist CVD, five crystal phases (<em>α</em>, <em>β</em>, <em>γ</em>, <em>ε</em>, and <em>δ</em>) of Ga<sub>2</sub>O<sub>3</sub> films have been successfully produced, and the properties of Ga<sub>2</sub>O<sub>3</sub> films can be easily tuned through doping and alloy engineering. Additionally, semiconductor devices have been fabricated using Ga<sub>2</sub>O<sub>3</sub> films grown by mist CVD. However, challenges remain in terms of doping uniformity, crystal phase purity, and stability. This paper reviews the advancements in mist CVD for the deposition of Ga<sub>2</sub>O<sub>3</sub>, covering mist CVD equipment design, Ga<sub>2</sub>O<sub>3</sub> crystal phase control, doping and alloy modulation, and device fabrication.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"49 ","pages":"Article 101604"},"PeriodicalIF":10.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The p-type doping is one of the main challenges of the emerging semiconductor β-Ga2O3 technology. Phosphorus (P) implantation has been recently reported as a novel route to achieve p-type conduction on Ga2O3 at room temperature. Here, P-implanted epilayers, grown onto c-plane sapphire revealed a pseudo-metallic behavior (ρ = 1.3–0.3 Ω cm) in the 300–600 K range with a hole carrier concentration of p ⁓ 4–6 × 1018 cm−3 and hole mobility of μ = 1.2–2.1 cm2/(V·s). At sufficiently low temperature, a metal-insulator transition arises together with an increase in the positive magnetoresistance, reaching up to 200 % (9 T) large positive magneto resistance effect at 2 K. It is suggested that an Anderson delocalization model explains the room temperature conduction, and the transition to an insulator state caused by random variation of potential related to the incorporated phosphorous in Ga2O3. We believe that the lack of shallow acceptors can be mitigated by promoting Anderson disorder through the incorporation of a high level of acceptor impurities.
p 型掺杂是新兴半导体 β-Ga2O3 技术面临的主要挑战之一。最近有报道称，磷植入是在室温下实现 Ga2O3 p 型传导的一种新方法。在这里，生长在 c 平面蓝宝石上的磷植入外延层在 300 - 600 K 范围内显示出假金属行为（ρ = 1.3 - 0.3 Ω-cm），空穴载流子浓度为 p ⁓ 4 - 6 ×1018 cm-3，空穴迁移率为 μ = 1.2 - 2.1 cm2/（V-s）。在足够低的温度下，会出现金属-绝缘体转变，同时正磁阻增加，在 2 K 时达到 200% (9 T) 的大正磁阻效应。有人认为，安德森析出模型可以解释室温传导，而向绝缘体状态的转变是由与 Ga2O3 中的磷结合相关的电位随机变化引起的。我们认为，可以通过加入高水平的受体杂质来促进安德森无序，从而缓解浅层受体的缺乏。
{"title":"Anderson disorder related p-type conductivity and metal-insulator transition in β-Ga2O3","authors":"Zeyu Chi , Se-Rim Park , Luka Burdiladze , Tamar Tchelidze , Jean-Michel Chauveau , Yves Dumont , Sang-Mo Koo , Zurab Kushitashvili , Amiran Bibilashvili , Gérard Guillot , Amador Pérez-Tomás , Xin-Ying Tsai , Fu-Gow Tarntair , Ray Hua Horng , Ekaterine Chikoidze","doi":"10.1016/j.mtphys.2024.101602","DOIUrl":"10.1016/j.mtphys.2024.101602","url":null,"abstract":"<div><div>The <em>p</em>-type doping is one of the main challenges of the emerging semiconductor <em>β-</em>Ga<sub>2</sub>O<sub>3</sub> technology. Phosphorus (P) implantation has been recently reported as a novel route to achieve <em>p</em>-type conduction on Ga<sub>2</sub>O<sub>3</sub> at room temperature. Here, P-implanted epilayers, grown onto <em>c</em>-plane sapphire revealed a pseudo-metallic behavior (<em>ρ</em> = 1.3–0.3 Ω cm) in the 300–600 K range with a hole carrier concentration of <em>p</em> ⁓ 4–6 × 10<sup>18</sup> cm<sup>−3</sup> and hole mobility of <em>μ</em> = 1.2–2.1 cm<sup>2</sup>/(V·s). At sufficiently low temperature, a metal-insulator transition arises together with an increase in the positive magnetoresistance, reaching up to 200 % (9 T) large positive magneto resistance effect at 2 K. It is suggested that an Anderson delocalization model explains the room temperature conduction, and the transition to an insulator state caused by random variation of potential related to the incorporated phosphorous in Ga<sub>2</sub>O<sub>3</sub>. We believe that the lack of shallow acceptors can be mitigated by promoting Anderson disorder through the incorporation of a high level of acceptor impurities.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"49 ","pages":"Article 101602"},"PeriodicalIF":10.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.mtphys.2024.101603
Xiaochang Xing , Yanxiang Wang , Jianchang Jiang , Lingling Wu , Xiaoyong Tian , Ying Li
Achieving effective control of thermal and mechanical distributions has been a long-standing goal, and metamaterials have emerged as a crucial tool for customizing functional structures to manipulate these physical fields. However, existing design paradigms do not apply to thermal-mechanical metamaterials that operate on thermal and mechanical fields simultaneously and independently. First, Due to the different geometric requirements imposed by the thermal and mechanical fields on the unit cells, there is a conflict between functional coupling and design coupling, which limits the design of thermal-mechanical metamaterials. Second, the fact that continuum mechanical equations do not remain invariant under general coordinate transformations hinders the application of conventional theories. Additionally, balancing minimal design costs, manufacturability, and optimal functionality remains a significant challenge. Here, we propose a global data-driven design method using Bayesian hyperparameter optimization. This method creates thermal-mechanical metamaterials from a large, pre-computed unit cell database. Our flexible method allows designing thermal-mechanical metamaterials with various functional combinations (e.g., cloaks, concentrators, and rotators) and shapes. Compared to traditional solutions, this approach balances manufacturability and functionality while offering unparalleled universality and low design costs. Experimental measurements validate the effectiveness of our method. Our approach can rapidly respond to new design scenarios and address design challenges related to the multi-physical effects.
{"title":"Data-driven design of thermal-mechanical multifunctional metamaterials","authors":"Xiaochang Xing , Yanxiang Wang , Jianchang Jiang , Lingling Wu , Xiaoyong Tian , Ying Li","doi":"10.1016/j.mtphys.2024.101603","DOIUrl":"10.1016/j.mtphys.2024.101603","url":null,"abstract":"<div><div>Achieving effective control of thermal and mechanical distributions has been a long-standing goal, and metamaterials have emerged as a crucial tool for customizing functional structures to manipulate these physical fields. However, existing design paradigms do not apply to thermal-mechanical metamaterials that operate on thermal and mechanical fields simultaneously and independently. First, Due to the different geometric requirements imposed by the thermal and mechanical fields on the unit cells, there is a conflict between functional coupling and design coupling, which limits the design of thermal-mechanical metamaterials. Second, the fact that continuum mechanical equations do not remain invariant under general coordinate transformations hinders the application of conventional theories. Additionally, balancing minimal design costs, manufacturability, and optimal functionality remains a significant challenge. Here, we propose a global data-driven design method using Bayesian hyperparameter optimization. This method creates thermal-mechanical metamaterials from a large, pre-computed unit cell database. Our flexible method allows designing thermal-mechanical metamaterials with various functional combinations (e.g., cloaks, concentrators, and rotators) and shapes. Compared to traditional solutions, this approach balances manufacturability and functionality while offering unparalleled universality and low design costs. Experimental measurements validate the effectiveness of our method. Our approach can rapidly respond to new design scenarios and address design challenges related to the multi-physical effects.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"49 ","pages":"Article 101603"},"PeriodicalIF":10.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.mtphys.2024.101598
Biao Zhang , Liming Quan , Zhihong Luo , Qiantong Li , Jianming Deng , Shuhang Yu , Wangxin Li , Mingmei Lin , Feng Yan , Dawei Wang , Dongyan Yu , Changbai Long , Laijun Liu
CaBi2Nb2O9 (CBNO) ceramics exhibit significant potential in the development of piezoelectric sensors suitable for extreme environments such as aerospace, metallurgy, and nuclear power plants. While previous studies have enhanced the piezoelectric response of CBNO ceramics, their insulating properties at high temperatures still require improvement. In this work, co-substitution of (Li0.5Bi0.5) at A site and Mn at B site was designed to improve the electrical properties of CBNO ceramics. Defect dipoles induced by the bound between Mn and oxygen vacancies restrict the movement of oxygen vacancies at high temperatures. Meanwhile, co-substitution of Ca by (Li0.5Bi0.5) reduces both the sintering temperature and volatilization of Bi2O3 during the sintering process. This modification results in an ultra-high TC of 928 °C and an exceptional resistivity of 2.85 MΩ cm at 600 °C for Ca0.96(Li0.5Bi0.5)0.04Bi2Nb1.98Mn0.02O9 ceramics. Furthermore, the ceramic exhibits excellent piezoelectric properties (d33 of 15.2 pC/N and kp of 6.9 %), ferroelectric properties (Pr of 9.42 μC/cm2), and thermal stability (degeneration of d33 only 6 % after annealing at 900 °C for 2 h). This work offers a practical strategy for simultaneously achieving both a high piezoelectric response and outstanding insulating properties in the CBNO system.
{"title":"Achieving ultra-high resistivity and outstanding piezoelectric properties by co-substitution in CaBi2Nb2O9 ceramics","authors":"Biao Zhang , Liming Quan , Zhihong Luo , Qiantong Li , Jianming Deng , Shuhang Yu , Wangxin Li , Mingmei Lin , Feng Yan , Dawei Wang , Dongyan Yu , Changbai Long , Laijun Liu","doi":"10.1016/j.mtphys.2024.101598","DOIUrl":"10.1016/j.mtphys.2024.101598","url":null,"abstract":"<div><div>CaBi<sub>2</sub>Nb<sub>2</sub>O<sub>9</sub> (CBNO) ceramics exhibit significant potential in the development of piezoelectric sensors suitable for extreme environments such as aerospace, metallurgy, and nuclear power plants. While previous studies have enhanced the piezoelectric response of CBNO ceramics, their insulating properties at high temperatures still require improvement. In this work, co-substitution of (Li<sub>0.5</sub>Bi<sub>0.5</sub>) at A site and Mn at B site was designed to improve the electrical properties of CBNO ceramics. Defect dipoles induced by the bound between Mn and oxygen vacancies restrict the movement of oxygen vacancies at high temperatures. Meanwhile, co-substitution of Ca by (Li<sub>0.5</sub>Bi<sub>0.5</sub>) reduces both the sintering temperature and volatilization of Bi<sub>2</sub>O<sub>3</sub> during the sintering process. This modification results in an ultra-high <em>T</em><sub>C</sub> of 928 °C and an exceptional resistivity of 2.85 MΩ cm at 600 °C for Ca<sub>0.96</sub>(Li<sub>0.5</sub>Bi<sub>0.5</sub>)<sub>0.04</sub>Bi<sub>2</sub>Nb<sub>1.98</sub>Mn<sub>0.02</sub>O<sub>9</sub> ceramics. Furthermore, the ceramic exhibits excellent piezoelectric properties (<em>d</em><sub>33</sub> of 15.2 pC/N and <em>k</em><sub>p</sub> of 6.9 %), ferroelectric properties (<em>P</em><sub>r</sub> of 9.42 μC/cm<sup>2</sup>), and thermal stability (degeneration of <em>d</em><sub>33</sub> only 6 % after annealing at 900 °C for 2 h). This work offers a practical strategy for simultaneously achieving both a high piezoelectric response and outstanding insulating properties in the CBNO system.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"49 ","pages":"Article 101598"},"PeriodicalIF":10.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.mtphys.2024.101600
Muhammad Tahir Sohail , Jinde Yin , Muhammad Abdullah , Muhammad Younis , Muhammad Naveed Anjum , Muhammad Tayyab Sohail , Roobaea Alroobaea , Imtiaz Ahmed , Yan Peiguang
High-power lasers operating at the 2 μm wavelength domain have gained considerable interest in recent times owing to their distinct characteristics and versatile applications in the field of medical and industrial precision processing. This article presents a comprehensive review of high-power lasers, beginning with an overview of rare-earth silica fiber as a critical component for high-power lasers performing at 2 μm. Subsequently, the research progress of three essential high-power laser technologies – continuous-wave (CW), pulsed, and single-frequency (SF) lasers – is thoroughly analyzed, highlighting their respective strengths and limitations. Moreover, the potential of combining silica fibers with Raman technology for effective wavelength extension in 2 μm lasers is explored. Furthermore, the article emphasizes the current challenges associated with the progression of high-power fiber lasers and outlines potential avenues for future advancements.
{"title":"Recent progress on high-power 2 μm fiber lasers: A comprehensive study of advancements, applications, and future perspectives","authors":"Muhammad Tahir Sohail , Jinde Yin , Muhammad Abdullah , Muhammad Younis , Muhammad Naveed Anjum , Muhammad Tayyab Sohail , Roobaea Alroobaea , Imtiaz Ahmed , Yan Peiguang","doi":"10.1016/j.mtphys.2024.101600","DOIUrl":"10.1016/j.mtphys.2024.101600","url":null,"abstract":"<div><div>High-power lasers operating at the 2 μm wavelength domain have gained considerable interest in recent times owing to their distinct characteristics and versatile applications in the field of medical and industrial precision processing. This article presents a comprehensive review of high-power lasers, beginning with an overview of rare-earth silica fiber as a critical component for high-power lasers performing at 2 μm. Subsequently, the research progress of three essential high-power laser technologies – continuous-wave (CW), pulsed, and single-frequency (SF) lasers – is thoroughly analyzed, highlighting their respective strengths and limitations. Moreover, the potential of combining silica fibers with Raman technology for effective wavelength extension in 2 μm lasers is explored. Furthermore, the article emphasizes the current challenges associated with the progression of high-power fiber lasers and outlines potential avenues for future advancements.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"49 ","pages":"Article 101600"},"PeriodicalIF":10.0,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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