Wenli Wang, Yicheng Chen, Bo Wang, Lisong Wang, Yongliang Han, W. Su, Zhongqiang Hu, Zhiguang Wang, Meilin Liu
Unidirectional magnetic anisotropy induced by exchange bias (EB) between ferromagnetic and antiferromagnetic layers is of paramount importance in various spintronic devices. Traditional setting and optimization of EB involves cooling through the Néel temperature of the antiferromagnets under biasing field in vacuum furnace which takes hours of time and could not realize localized control of EB. Here, we report an alternative process to configure EB by injection of microsecond current impulse for locally heating of the heterostructure. 180‐degree exchange bias switching has been realized in both anisotropic magnetoresistance and giant magnetoresistance units, resulting in tunable magnetic field sensing functionalities. This mechanism for pinpoint control of EB provides more freedom for design and optimization of various sensing and logic spintronics.This article is protected by copyright. All rights reserved.
{"title":"Locally reconfigurable exchange bias for tunable spintronics by pulsed current injection","authors":"Wenli Wang, Yicheng Chen, Bo Wang, Lisong Wang, Yongliang Han, W. Su, Zhongqiang Hu, Zhiguang Wang, Meilin Liu","doi":"10.1002/pssr.202300303","DOIUrl":"https://doi.org/10.1002/pssr.202300303","url":null,"abstract":"Unidirectional magnetic anisotropy induced by exchange bias (EB) between ferromagnetic and antiferromagnetic layers is of paramount importance in various spintronic devices. Traditional setting and optimization of EB involves cooling through the Néel temperature of the antiferromagnets under biasing field in vacuum furnace which takes hours of time and could not realize localized control of EB. Here, we report an alternative process to configure EB by injection of microsecond current impulse for locally heating of the heterostructure. 180‐degree exchange bias switching has been realized in both anisotropic magnetoresistance and giant magnetoresistance units, resulting in tunable magnetic field sensing functionalities. This mechanism for pinpoint control of EB provides more freedom for design and optimization of various sensing and logic spintronics.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77712411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. S. Kurochkin, V. Sychev, A. V. Gritsienko, D. Bi
Nano‐ and microcrystals of diamond are attractive for optical thermometry applications and possess unique optical properties as well as high chemical stability and biocompatibility. For biological application there are interest of diamonds with color centers that emit in the biological transparency window. One such defect is nickel‐related color centers that radiate in the near‐infrared range (1.4‐eV Ni centers), but have not yet been sufficiently investigated. This study reports the optical characteristics of HPHT diamond microcrystals with average sizes of 4 μm and 30 μm containing 1.4‐eV Ni centers. The temperature dependence of the spectral and temporal properties of Ni center emissions in the range from room temperature to 85 °C was demonstrated and thereby the possibility of appliance these centers as temperature sensors. The relative temperature sensitivities of luminescence peak intensity and lifetime for Ni centers were found to be 1.3% K−1 and 0.42% K−1, respectively. Moreover, the temperature determination accuracy reached better than 1 K.This article is protected by copyright. All rights reserved.
金刚石的纳米晶体和微晶体在光学测温应用中具有吸引力，具有独特的光学特性以及高化学稳定性和生物相容性。对于生物应用，人们对具有在生物透明窗口中发光的色心的金刚石感兴趣。其中一个缺陷是镍相关的色心，它在近红外范围内辐射(1.4 eV镍中心)，但尚未得到充分的研究。本研究报道了平均尺寸为4 μm和30 μm的含1.4 eV Ni中心的HPHT金刚石微晶的光学特性。在室温至85°C范围内，Ni中心发射光谱和时间特性的温度依赖性得到了证明，从而证明了应用这些中心作为温度传感器的可能性。Ni中心发光峰强度和寿命的相对温度敏感度分别为1.3% K−1和0.42% K−1。测温精度达到1 K以上。这篇文章受版权保护。版权所有。
{"title":"Nickel‐related centers in HPHT microdiamonds for near‐infrared luminescent thermometry","authors":"N. S. Kurochkin, V. Sychev, A. V. Gritsienko, D. Bi","doi":"10.1002/pssr.202300277","DOIUrl":"https://doi.org/10.1002/pssr.202300277","url":null,"abstract":"Nano‐ and microcrystals of diamond are attractive for optical thermometry applications and possess unique optical properties as well as high chemical stability and biocompatibility. For biological application there are interest of diamonds with color centers that emit in the biological transparency window. One such defect is nickel‐related color centers that radiate in the near‐infrared range (1.4‐eV Ni centers), but have not yet been sufficiently investigated. This study reports the optical characteristics of HPHT diamond microcrystals with average sizes of 4 μm and 30 μm containing 1.4‐eV Ni centers. The temperature dependence of the spectral and temporal properties of Ni center emissions in the range from room temperature to 85 °C was demonstrated and thereby the possibility of appliance these centers as temperature sensors. The relative temperature sensitivities of luminescence peak intensity and lifetime for Ni centers were found to be 1.3% K−1 and 0.42% K−1, respectively. Moreover, the temperature determination accuracy reached better than 1 K.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"102 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83750034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cs3Bi2I9 (CBI) is a promising material for direct X‐ray detectors. However, for the solution method, due to the difference in the chemical potential of Cs+, Bi3+, I‐ ions in the solvent, the composition of Cs3Bi2I9 single crystals (SC) prepared by the solution method often deviates from the stoichiometric ratio, resulting in the formation of many defects in the material, which degrades the quality of the SC. In this work, Br‐ and Cl‐ were used as dopants to produce CBI SCs by the top seed solution method. It can be speculated that the dopant ions could reduce the VI defects in the CBI by means of density functional theory (DFT) calculations. The carrier lifetimes of CBI SCs doped with Br‐ and Cl‐ have been increased to 41.7 ns and 13.0 ns, respectively. Meanwhile, the defect densities of the SCs were reduced to 1.02×109 cm‐3 and 1.85×109 cm‐3, respectively. X‐ray detectors based on Br‐doped CBI and Cl‐doped CBI SCs exhibited high X‐ray sensitivity of 23071.3 μC Gyair ‐1cm‐2 and 18525.3 μC Gyair ‐1cm‐2 at an electric field of 40 V mm‐1, respectively. In addition, the X‐ray detection limit reaches 1.07 nGyairs‐1 and 1.35 nGyairs‐1 at an electric field of 2.5 V mm‐1, respectively.This article is protected by copyright. All rights reserved.
Cs3Bi2I9 (CBI)是一种很有前途的X射线直接探测器材料。然而，溶液法制备的Cs3Bi2I9单晶(SC)由于溶剂中Cs+、Bi3+、I‐离子的化学势不同，其组成往往偏离化学计量比，导致材料中形成许多缺陷，从而降低了SC的质量。本研究以Br‐和Cl‐为掺杂剂，采用top seed溶液法制备了CBI SC。通过密度泛函理论(DFT)计算可以推测，掺杂离子可以减少CBI中的VI缺陷。掺入Br‐和Cl‐的CBI SCs的载流子寿命分别提高到41.7 ns和13.0 ns。同时，sc的缺陷密度分别降至1.02×109 cm‐3和1.85×109 cm‐3。基于Br掺杂CBI和Cl掺杂CBI sc的X射线探测器在40 V mm‐1电场下分别表现出23071.3 μC Gyair‐1cm‐2和18525.3 μC Gyair‐1cm‐2的高X射线灵敏度。此外，在2.5 V mm‐1电场下，X射线检测极限分别达到1.07和1.35 nGyairs‐1。这篇文章受版权保护。版权所有。
{"title":"Doping modification of Cs3Bi2I9 single crystals for high performance X‐ray detectors","authors":"Anfeng Li, Manman Yang, Aoxi He, Peng Tang, X. Hao, Lili Wu, Wenbo Tian, Dingyu Yang, Jingquan Zhang","doi":"10.1002/pssr.202300306","DOIUrl":"https://doi.org/10.1002/pssr.202300306","url":null,"abstract":"Cs3Bi2I9 (CBI) is a promising material for direct X‐ray detectors. However, for the solution method, due to the difference in the chemical potential of Cs+, Bi3+, I‐ ions in the solvent, the composition of Cs3Bi2I9 single crystals (SC) prepared by the solution method often deviates from the stoichiometric ratio, resulting in the formation of many defects in the material, which degrades the quality of the SC. In this work, Br‐ and Cl‐ were used as dopants to produce CBI SCs by the top seed solution method. It can be speculated that the dopant ions could reduce the VI defects in the CBI by means of density functional theory (DFT) calculations. The carrier lifetimes of CBI SCs doped with Br‐ and Cl‐ have been increased to 41.7 ns and 13.0 ns, respectively. Meanwhile, the defect densities of the SCs were reduced to 1.02×109 cm‐3 and 1.85×109 cm‐3, respectively. X‐ray detectors based on Br‐doped CBI and Cl‐doped CBI SCs exhibited high X‐ray sensitivity of 23071.3 μC Gyair\u0000‐1cm‐2 and 18525.3 μC Gyair\u0000‐1cm‐2 at an electric field of 40 V mm‐1, respectively. In addition, the X‐ray detection limit reaches 1.07 nGyairs‐1 and 1.35 nGyairs‐1 at an electric field of 2.5 V mm‐1, respectively.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82401496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Van der Waals (vdW) heterostructures based on two‐dimensional materials and conventional group IV semiconductors have shown great potential for wide spectrum, highly sensitive photodetectors owing to their broadband absorption, high‐quality interface, and compatibility with complementary metal‐oxide‐semiconductor (CMOS) technology. Here, we propose a unique heterojunction phototransistor composed of an indium tin oxide (ITO) capped p‐WSe2/n‐Ge vdW heterojunction serving as the emitter and an annular shallow‐trench Al/Ge Schottky junction acting as the collector. The mixed‐dimensional phototransistor exhibiting high responsivities up to 66 A W‐1 at 405 nm and 124 A W‐1 at 1550 nm demonstrates a brilliant wide spectrum response performance. The high photocurrent gain can be attributed to the extra‐large carrier injection ratio of the heterojunction. The short transient response time in the order of 100 µs is achieved with the modified lateral electrical field by the annular shallow‐trench Schottky barrier collector. The combination of p‐WSe2/n‐Ge vdW heterojunction and the annular shallow‐trench Al/n‐Ge Schottky junction renders a low‐cost, high‐performance photodetector fabricated in a simple and CMOS compatible way for visible to short wave infrared (SWIR) broadband detection.This article is protected by copyright. All rights reserved.
{"title":"Visible to Short Wave Infrared Broadband p‐WSe2/n‐Ge Heterojunction Phototransistor with an Annular Shallow‐Trench Schottky Barrier Collector","authors":"Shuo Li, Xinwei Cai, Haokun Ding, Qiang Wu, Songsong Wu, Guangyang Lin, Wei Huang, Songyan Chen, Cheng Li","doi":"10.1002/pssr.202300276","DOIUrl":"https://doi.org/10.1002/pssr.202300276","url":null,"abstract":"Van der Waals (vdW) heterostructures based on two‐dimensional materials and conventional group IV semiconductors have shown great potential for wide spectrum, highly sensitive photodetectors owing to their broadband absorption, high‐quality interface, and compatibility with complementary metal‐oxide‐semiconductor (CMOS) technology. Here, we propose a unique heterojunction phototransistor composed of an indium tin oxide (ITO) capped p‐WSe2/n‐Ge vdW heterojunction serving as the emitter and an annular shallow‐trench Al/Ge Schottky junction acting as the collector. The mixed‐dimensional phototransistor exhibiting high responsivities up to 66 A W‐1 at 405 nm and 124 A W‐1 at 1550 nm demonstrates a brilliant wide spectrum response performance. The high photocurrent gain can be attributed to the extra‐large carrier injection ratio of the heterojunction. The short transient response time in the order of 100 µs is achieved with the modified lateral electrical field by the annular shallow‐trench Schottky barrier collector. The combination of p‐WSe2/n‐Ge vdW heterojunction and the annular shallow‐trench Al/n‐Ge Schottky junction renders a low‐cost, high‐performance photodetector fabricated in a simple and CMOS compatible way for visible to short wave infrared (SWIR) broadband detection.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"147 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86771912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hongjie Zhang, Xiang Li, Tong Qin, Lan Zhang, Wei Du, Peining Li, Tao Wang
Phonon polaritons (PhPs) in two‐dimensional van der Waals (vdW) crystals exhibit strong spatial confinement and long polariton lifetimes, making them promising for developing novel nanophotonic devices at mid‐infrared frequencies. Here, using α‐phase molybdenum trioxide (α‐MoO3) microdisks, we have demonstrated in‐plane anisotropic PhP resonances with degree of polarization (DoP) of almost 100% from far field observation. Such in‐plane polarization‐dependent PhP resonances, originating from the anisotropic crystal structure of α‐MoO3, are readily tuned by the disk length and fits well to numerical simulations. Our findings show new possibility for engineering in‐plane polarizers based on vdW crystals and may promote the development of functional polarization‐sensitive optoelectronic devices at mid‐infrared frequencies.This article is protected by copyright. All rights reserved.
{"title":"In‐Plane Anisotropic Phonon‐Polaritonic Resonances with α‐MoO3 microdisks","authors":"Hongjie Zhang, Xiang Li, Tong Qin, Lan Zhang, Wei Du, Peining Li, Tao Wang","doi":"10.1002/pssr.202300302","DOIUrl":"https://doi.org/10.1002/pssr.202300302","url":null,"abstract":"Phonon polaritons (PhPs) in two‐dimensional van der Waals (vdW) crystals exhibit strong spatial confinement and long polariton lifetimes, making them promising for developing novel nanophotonic devices at mid‐infrared frequencies. Here, using α‐phase molybdenum trioxide (α‐MoO3) microdisks, we have demonstrated in‐plane anisotropic PhP resonances with degree of polarization (DoP) of almost 100% from far field observation. Such in‐plane polarization‐dependent PhP resonances, originating from the anisotropic crystal structure of α‐MoO3, are readily tuned by the disk length and fits well to numerical simulations. Our findings show new possibility for engineering in‐plane polarizers based on vdW crystals and may promote the development of functional polarization‐sensitive optoelectronic devices at mid‐infrared frequencies.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"152 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86220891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The high density of two‐dimensional electron gas (2DEG) in InAlN/AlN/GaN heterostructures results in significant occupation of higher subbands, it is thus imperative to consider multi‐subband occupation and inter‐subband scattering in the calculations of polar optical phonon (POP) scattering. The physical parameters, such as subband energies, wave functions of the four lowest subbands, and Fermi level of InAlN/AlN/GaN heterostructures, are calculated by solving the Schrödinger‐Poisson equations and applied to the multi‐subband POP scattering model. The dependence of mobility, which is limited by multi‐subband POP scattering, on temperature and 2DEG density is studied. The results show that multi‐subband occupation and inter‐subband scattering play important roles in electron transport. The higher subbands contribute 26% to room‐temperature electron mobility. Two simplified POP scattering models, which either ignore multi‐subband occupation or simplify the in‐scattering processes are evaluated. The results show that both simplified models introduce significant deviations in the mobilities that are limited by POP scattering. The relative magnitudes of mobility in each subband depend on the energy dependence of momentum relaxation time and the energy distribution of each subband.This article is protected by copyright. All rights reserved.
{"title":"Multi‐subband Polar Optical Phonon Scattering in InAlN/AlN/GaN Heterostructures","authors":"Qun Li, Yao Li, Yachao Zhang, Jincheng Zhang","doi":"10.1002/pssr.202300238","DOIUrl":"https://doi.org/10.1002/pssr.202300238","url":null,"abstract":"The high density of two‐dimensional electron gas (2DEG) in InAlN/AlN/GaN heterostructures results in significant occupation of higher subbands, it is thus imperative to consider multi‐subband occupation and inter‐subband scattering in the calculations of polar optical phonon (POP) scattering. The physical parameters, such as subband energies, wave functions of the four lowest subbands, and Fermi level of InAlN/AlN/GaN heterostructures, are calculated by solving the Schrödinger‐Poisson equations and applied to the multi‐subband POP scattering model. The dependence of mobility, which is limited by multi‐subband POP scattering, on temperature and 2DEG density is studied. The results show that multi‐subband occupation and inter‐subband scattering play important roles in electron transport. The higher subbands contribute 26% to room‐temperature electron mobility. Two simplified POP scattering models, which either ignore multi‐subband occupation or simplify the in‐scattering processes are evaluated. The results show that both simplified models introduce significant deviations in the mobilities that are limited by POP scattering. The relative magnitudes of mobility in each subband depend on the energy dependence of momentum relaxation time and the energy distribution of each subband.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"284 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77734082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A Fano resonator using black phosphorus, capable of tuning the operating band while possessing high sensitivity, is proposed. A ring and a groove are respectively etched above and below the main channel to produce the Fano resonance, resulting in a highly sensitive Fano resonator. Such a sensor can capture slight changes in the surrounding environment. Moreover, adding black phosphorus into the ring above the channel and into the groove below the channel, the electron doping of black phosphorus can be altered to adjust the resonant frequency of the Fano resonator. The shiftable frequency of the Fano resonator designed herein can reach 57 GHz at the second‐order resonance around 1.895 THz, an ability highly attractive in fields that require high sensitivity and adjustability. It is essential in the area of integrated electronics, offers fresh perspectives for innovations in integrated electronic gadgets, and paves the way for flexible terahertz systems.
{"title":"A Tunable Fano Resonator with High Sensitivity Based on Black Phosphorus in the Terahertz Band","authors":"Hao Zhang, Xue-shi Li, Weijun Sun, Yonghui Huang, Yuanmei Xu, K. Wen, Naixing Feng","doi":"10.1002/pssr.202300207","DOIUrl":"https://doi.org/10.1002/pssr.202300207","url":null,"abstract":"A Fano resonator using black phosphorus, capable of tuning the operating band while possessing high sensitivity, is proposed. A ring and a groove are respectively etched above and below the main channel to produce the Fano resonance, resulting in a highly sensitive Fano resonator. Such a sensor can capture slight changes in the surrounding environment. Moreover, adding black phosphorus into the ring above the channel and into the groove below the channel, the electron doping of black phosphorus can be altered to adjust the resonant frequency of the Fano resonator. The shiftable frequency of the Fano resonator designed herein can reach 57 GHz at the second‐order resonance around 1.895 THz, an ability highly attractive in fields that require high sensitivity and adjustability. It is essential in the area of integrated electronics, offers fresh perspectives for innovations in integrated electronic gadgets, and paves the way for flexible terahertz systems.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80953399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xingwang Chen, Lei Chen, Lihao Sun, Tao Wei, Yun Ling, Jing Hu, Miao Cheng, Qianqian Liu, Ruirui Wang, Wanfei Li, Bo Liu
Ge2Sb2Te5 thin film is investigated as a positive heat‐mode resist and environmentally‐friendlily FeCl3 solution is as means an efficient developer. The corrosion selectivity of exposed to as‐deposited thin film reaches 2.3 and the etching selectivity of Si to Ge2Sb2Te5 thin film is as high as 15.75. Moreover, high‐resolution nanostructures with minimum linewidth of 180 nm and period of 400 nm are obtained along with high resolution of 130 nm. In addition, the mechanism of corrosion selectivity between as‐deposited and exposed thin film is further elucidated based on microstructural analysis. Hence, Ge2Sb2Te5 thin film is a promising positive resist for high‐resolution direct laser writing lithography.This article is protected by copyright. All rights reserved.
{"title":"Ge2Sb2Te5 thin film as a promising heat‐mode resist for high‐resolution direct laser writing lithography","authors":"Xingwang Chen, Lei Chen, Lihao Sun, Tao Wei, Yun Ling, Jing Hu, Miao Cheng, Qianqian Liu, Ruirui Wang, Wanfei Li, Bo Liu","doi":"10.1002/pssr.202300262","DOIUrl":"https://doi.org/10.1002/pssr.202300262","url":null,"abstract":"Ge2Sb2Te5 thin film is investigated as a positive heat‐mode resist and environmentally‐friendlily FeCl3 solution is as means an efficient developer. The corrosion selectivity of exposed to as‐deposited thin film reaches 2.3 and the etching selectivity of Si to Ge2Sb2Te5 thin film is as high as 15.75. Moreover, high‐resolution nanostructures with minimum linewidth of 180 nm and period of 400 nm are obtained along with high resolution of 130 nm. In addition, the mechanism of corrosion selectivity between as‐deposited and exposed thin film is further elucidated based on microstructural analysis. Hence, Ge2Sb2Te5 thin film is a promising positive resist for high‐resolution direct laser writing lithography.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88591643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Minseon Gu, Keun Wook Lee, Beomjin Park, Beom Soo Joo, Young Jun Chang, Dong-Wook Park, Moonsup Han
Hybrid 2D/0D structures with various 2D materials and 0D quantum dots (QDs) have been studied to overcome the limitations of 2D materials. In this work, a hybrid structure with MoS2 and silicon quantum dots (Si QDs) as a photodetector is developed. The I–V transfer characteristics show a threshold voltage shift after decorating Si QDs on MoS2, which results from an n‐type doping effect to the MoS2 channel from the Si QDs. The field‐effect mobility of the MoS2/Si QDs device is increased by ≈5.8 times compared with that of the bare MoS2 device. It is understood that the mobility enhancement is attributed to the surface defect passivation of MoS2 at the interface with Si QDs. It is observed that the photoresponsivity of the MoS2/Si QDs structure is improved by ≈7.7 times compared with that of the bare MoS2 device under 500 nm illumination. Additionally, it is observed that the photoluminescence (PL) intensity of MoS2 is increased about 4.5 times after decoration of Si QDs. The band alignment as type I at the interface between the Si QDs and MoS2 is interpreted. The mobility enhancement and the photoexcited charge transfer (CT) between the MoS2 and the Si QDs due to the illumination lead to enhancing the photoresponsivity of the MoS2/Si QDs hybrid structure.
{"title":"Photoresponsivity Enhancement of Monolayer MoS2 by Silicon Quantum Dots","authors":"Minseon Gu, Keun Wook Lee, Beomjin Park, Beom Soo Joo, Young Jun Chang, Dong-Wook Park, Moonsup Han","doi":"10.1002/pssr.202300220","DOIUrl":"https://doi.org/10.1002/pssr.202300220","url":null,"abstract":"Hybrid 2D/0D structures with various 2D materials and 0D quantum dots (QDs) have been studied to overcome the limitations of 2D materials. In this work, a hybrid structure with MoS2 and silicon quantum dots (Si QDs) as a photodetector is developed. The I–V transfer characteristics show a threshold voltage shift after decorating Si QDs on MoS2, which results from an n‐type doping effect to the MoS2 channel from the Si QDs. The field‐effect mobility of the MoS2/Si QDs device is increased by ≈5.8 times compared with that of the bare MoS2 device. It is understood that the mobility enhancement is attributed to the surface defect passivation of MoS2 at the interface with Si QDs. It is observed that the photoresponsivity of the MoS2/Si QDs structure is improved by ≈7.7 times compared with that of the bare MoS2 device under 500 nm illumination. Additionally, it is observed that the photoluminescence (PL) intensity of MoS2 is increased about 4.5 times after decoration of Si QDs. The band alignment as type I at the interface between the Si QDs and MoS2 is interpreted. The mobility enhancement and the photoexcited charge transfer (CT) between the MoS2 and the Si QDs due to the illumination lead to enhancing the photoresponsivity of the MoS2/Si QDs hybrid structure.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81764581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Ermolaev, Ying Xie, Liu Qian, Mikhail K. Tatmyshevskiy, A. Slavich, Aleksey Arsenin, Jin Zhang, V. Volkov, A. Chernov
Two‐dimensional materials are the fundamental building blocks for modern optoelectronics and photonics. Optically anisotropic monolayers give even more flexibility in device design and performance. However, the random orientation of optical axes in the large‐scale samples prevents anisotropic monolayers from widespread use. The alternative structure is a monolayer of aligned single‐walled carbon nanotubes (SWCNTs) with an anisotropic dielectric tensor. Here, we measure aligned SWCNTs monolayer anisotropic optical constants in a broad spectral range (250 – 1700 nm) for the first time. We discovered that it has a large birefringence of Δn ∽ 0.2 and a high dichroism of Δk ∽ 0.4. Moreover, we demonstrated that aligned SWCNTs monolayer optical response could be described by an effective medium approximation using the graphene dielectric function. Besides, it gives a universal approach for a determination of carbon concentration in nanotubes structures. It also applies for other types of carbon nanotubes, such as multi‐walled and randomly oriented carbon nanotubes arrays. Hence, our results add aligned SWCNTs monolayer optical constants to the optical anisotropy database, which facilitates the longstanding challenge of using one‐dimensional structures in two dimensions, and provide a rapid characterization method for carbon nanotubes.This article is protected by copyright. All rights reserved.
{"title":"Anisotropic optical properties of monolayer aligned single‐walled carbon nanotubes","authors":"G. Ermolaev, Ying Xie, Liu Qian, Mikhail K. Tatmyshevskiy, A. Slavich, Aleksey Arsenin, Jin Zhang, V. Volkov, A. Chernov","doi":"10.1002/pssr.202300199","DOIUrl":"https://doi.org/10.1002/pssr.202300199","url":null,"abstract":"Two‐dimensional materials are the fundamental building blocks for modern optoelectronics and photonics. Optically anisotropic monolayers give even more flexibility in device design and performance. However, the random orientation of optical axes in the large‐scale samples prevents anisotropic monolayers from widespread use. The alternative structure is a monolayer of aligned single‐walled carbon nanotubes (SWCNTs) with an anisotropic dielectric tensor. Here, we measure aligned SWCNTs monolayer anisotropic optical constants in a broad spectral range (250 – 1700 nm) for the first time. We discovered that it has a large birefringence of Δn ∽ 0.2 and a high dichroism of Δk ∽ 0.4. Moreover, we demonstrated that aligned SWCNTs monolayer optical response could be described by an effective medium approximation using the graphene dielectric function. Besides, it gives a universal approach for a determination of carbon concentration in nanotubes structures. It also applies for other types of carbon nanotubes, such as multi‐walled and randomly oriented carbon nanotubes arrays. Hence, our results add aligned SWCNTs monolayer optical constants to the optical anisotropy database, which facilitates the longstanding challenge of using one‐dimensional structures in two dimensions, and provide a rapid characterization method for carbon nanotubes.This article is protected by copyright. All rights reserved.","PeriodicalId":20059,"journal":{"name":"physica status solidi (RRL) – Rapid Research Letters","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89739992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：