Pub Date : 2026-01-31DOI: 10.1021/acsphotonics.5c02501
Leo Guery, Falco Bijloo, Peter M. Kraus
Digital holographic microscopy (DHM) is a successful technique frequently used to assess the phase in imaging experiments. Combining DHM with nonlinear generation opens the possibility of measuring phases in nonlinear processes such as high-harmonic generation and characterizing nanostructures with an increased sensitivity. In this paper, we demonstrate that the combination of DHM and harmonic generation from solids can be used to reliably perform 3D reconstructions of samples and also investigate structural parameters of subwavelength periodic structures with improved accuracy. We were able to discriminate gratings etched in silicon, with only a few tens of nanometers change in critical dimension, down to a pitch of 400 nm, which is well below the wavelength of the near-infrared (NIR) probing laser source. This technique can in principle be used with all high-harmonic-emitting materials and is expected to reach even larger gains in resolution by probing higher-order harmonics. These results pave the way for sensing of subwavelength structures via nonlinear light generation, for instance, in the semiconductor industry.
{"title":"Digital Holography Using Harmonic Generation from Solids for Reconstruction of Subwavelength Nanostructures","authors":"Leo Guery, Falco Bijloo, Peter M. Kraus","doi":"10.1021/acsphotonics.5c02501","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02501","url":null,"abstract":"Digital holographic microscopy (DHM) is a successful technique frequently used to assess the phase in imaging experiments. Combining DHM with nonlinear generation opens the possibility of measuring phases in nonlinear processes such as high-harmonic generation and characterizing nanostructures with an increased sensitivity. In this paper, we demonstrate that the combination of DHM and harmonic generation from solids can be used to reliably perform 3D reconstructions of samples and also investigate structural parameters of subwavelength periodic structures with improved accuracy. We were able to discriminate gratings etched in silicon, with only a few tens of nanometers change in critical dimension, down to a pitch of 400 nm, which is well below the wavelength of the near-infrared (NIR) probing laser source. This technique can in principle be used with all high-harmonic-emitting materials and is expected to reach even larger gains in resolution by probing higher-order harmonics. These results pave the way for sensing of subwavelength structures via nonlinear light generation, for instance, in the semiconductor industry.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"90 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-30DOI: 10.1021/acsphotonics.5c02359
Nan Sun, Chang Niu, Zhibo Zhou, Qian Cao, Jican Hao, Hao Geng, Ning Fang, Han Zhang, Lei Wang, Ziyao Zhou
Conventional voltage- or current-driven spintronic devices suffer from high power consumption and integration challenges, necessitating the development of alternative, energy-efficient pathways for spin control. Here, we demonstrate a photovoltaic tunable h-BN/Fe3GeTe2 (FGT)/n-Si magnetic heterostructure, exhibiting a reversible suppression of ∼25% in saturation magnetization (MS) near the Curie temperature. At 140 K, continuous illumination switches the FGT layer from a ferromagnetic to a paramagnetic state, demonstrating the effectiveness of photovoltaic control over the magnetic order. First-principles calculations reveal that photogenerated electrons in the n-Si are injected into the adjacent FGT layer, partially occupying minority-spin Fe-3d orbitals at a doping level of 0.1 electrons per atom, thereby reducing the total magnetic moment by 5–10% and weakening spin polarization and ferromagnetic exchange. Time-resolved Hall measurements confirm excellent cycling stability and reversibility of this modulation. This work integrates photovoltaic devices with emerging 2D magnetic materials, unlocking sunlight-tunable magnetic memory and CMOS-compatible spin-logic architectures, and offering a pathway toward ultralow-power, optically programmable spintronics.
{"title":"Photovoltaic Modulation of Magneto-Transport in Fe3GeTe2/n-Si van der Waals Heterostructures via Interfacial Photoelectron Transfer","authors":"Nan Sun, Chang Niu, Zhibo Zhou, Qian Cao, Jican Hao, Hao Geng, Ning Fang, Han Zhang, Lei Wang, Ziyao Zhou","doi":"10.1021/acsphotonics.5c02359","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02359","url":null,"abstract":"Conventional voltage- or current-driven spintronic devices suffer from high power consumption and integration challenges, necessitating the development of alternative, energy-efficient pathways for spin control. Here, we demonstrate a photovoltaic tunable h-BN/Fe<sub>3</sub>GeTe<sub>2</sub> (FGT)/n-Si magnetic heterostructure, exhibiting a reversible suppression of ∼25% in saturation magnetization (M<sub>S</sub>) near the Curie temperature. At 140 K, continuous illumination switches the FGT layer from a ferromagnetic to a paramagnetic state, demonstrating the effectiveness of photovoltaic control over the magnetic order. First-principles calculations reveal that photogenerated electrons in the n-Si are injected into the adjacent FGT layer, partially occupying minority-spin Fe-3d orbitals at a doping level of 0.1 electrons per atom, thereby reducing the total magnetic moment by 5–10% and weakening spin polarization and ferromagnetic exchange. Time-resolved Hall measurements confirm excellent cycling stability and reversibility of this modulation. This work integrates photovoltaic devices with emerging 2D magnetic materials, unlocking sunlight-tunable magnetic memory and CMOS-compatible spin-logic architectures, and offering a pathway toward ultralow-power, optically programmable spintronics.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"81 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-30DOI: 10.1021/acsphotonics.5c02338
Guangbo Zhang, Sisi Zhou, Ye Fang, Xuefeng Sun, Qianglong Yang, Chao Zhang, Rui Hu, Jiaqing Guo, Binglin Shen, Yuankai Guo, Can Zhao, Yan Huang, Weiguang Zheng, Zhixin Cong, Liwei Liu
There is an urgent need for volumetric microscopy techniques that can provide depth information while reducing scanning frequency. Since its proposal in 2010, the abruptly autofocusing beam (AAB) has attracted significant research interest owing to its distinctive autofocusing properties. However, efforts to generate AABs with both extended depth of field and depth-resolving capabilities continue to face major challenges. In this study, we present a volumetric two-photon confocal microscopy (TPCM) system based on power-exponent-phase vortex autofocusing beams (PVABs), which demonstrates depth-resolving functionality. The power-exponent-phase vortex (PV) enhances the axial imaging range, significantly increasing acquisition speed. PVABs serve as excitation sources to illuminate the specimen, with depth information extracted from variations in their side lobes. The depth-resolving range of this volumetric TPCM system reaches up to 100 μm, approximately 10 times greater than that of AABs. Compared with Bessel-beam-based TPCM, this approach offers superior depth-resolving performance and requires fewer scans than traditional Gaussian-beam-based TPCM. Experimental comparisons show that the imaging speed of the PVAB-based TPCM system is approximately 100 times faster than that of conventional Gaussian TPCM. This depth-resolved, high-speed volumetric imaging technique holds strong potential for investigating spatial distribution and dynamic processes in neural biology.
{"title":"Depth-Resolved Volumetric Two-Photon Fluorescence Microscopy Based on Power-Exponent-Phase Vortex Autofocusing Beam","authors":"Guangbo Zhang, Sisi Zhou, Ye Fang, Xuefeng Sun, Qianglong Yang, Chao Zhang, Rui Hu, Jiaqing Guo, Binglin Shen, Yuankai Guo, Can Zhao, Yan Huang, Weiguang Zheng, Zhixin Cong, Liwei Liu","doi":"10.1021/acsphotonics.5c02338","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02338","url":null,"abstract":"There is an urgent need for volumetric microscopy techniques that can provide depth information while reducing scanning frequency. Since its proposal in 2010, the abruptly autofocusing beam (AAB) has attracted significant research interest owing to its distinctive autofocusing properties. However, efforts to generate AABs with both extended depth of field and depth-resolving capabilities continue to face major challenges. In this study, we present a volumetric two-photon confocal microscopy (TPCM) system based on power-exponent-phase vortex autofocusing beams (PVABs), which demonstrates depth-resolving functionality. The power-exponent-phase vortex (PV) enhances the axial imaging range, significantly increasing acquisition speed. PVABs serve as excitation sources to illuminate the specimen, with depth information extracted from variations in their side lobes. The depth-resolving range of this volumetric TPCM system reaches up to 100 μm, approximately 10 times greater than that of AABs. Compared with Bessel-beam-based TPCM, this approach offers superior depth-resolving performance and requires fewer scans than traditional Gaussian-beam-based TPCM. Experimental comparisons show that the imaging speed of the PVAB-based TPCM system is approximately 100 times faster than that of conventional Gaussian TPCM. This depth-resolved, high-speed volumetric imaging technique holds strong potential for investigating spatial distribution and dynamic processes in neural biology.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"282 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The integration of optofluidic chips for manipulating light and liquids has catalyzed significant advances across various fields, including biology, medicine, chemistry, and display technologies. In this study, we propose an integrated platform for dynamic light field control by combining optofluidics with a cholesteric liquid crystal polymer template (CLCPT). We begin by investigating the dynamic tunability of CLCPT reflective bands embedded in a microfluidic chip, where the refractive index (RI) of the liquid can be tuned in real time across the visible spectrum. Next, we employ liquid crystal photoalignment to geometrically phase-encode the CLCPT and integrate it into a microfluidic channel, creating planar optical devices that leverage liquid RI variations to control the optical behavior. As examples, we demonstrate on-demand tunable planar optics such as q-plates and lenses. Finally, we integrated CLCPT with an optofluidic system for dynamic color displays, thereby expanding the range of display capabilities. This dynamic CLCPT optofluidic platform represents a promising route for controlling optical fields and, when combined with large-scale microfluidic integration, has potential applications in dynamic displays, imaging, holography, and sensing.
{"title":"An Optofluidic Platform Based on the Geometric Phase of Cholesteric Liquid Crystals for Dynamic Light Field Control","authors":"Shi-Long Li, Wei-Xiang Xiu, Liang Liu, Sen-Sen Li, Xuejia Hu, Lu-Jian Chen","doi":"10.1021/acsphotonics.5c02289","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02289","url":null,"abstract":"The integration of optofluidic chips for manipulating light and liquids has catalyzed significant advances across various fields, including biology, medicine, chemistry, and display technologies. In this study, we propose an integrated platform for dynamic light field control by combining optofluidics with a cholesteric liquid crystal polymer template (CLCPT). We begin by investigating the dynamic tunability of CLCPT reflective bands embedded in a microfluidic chip, where the refractive index (RI) of the liquid can be tuned in real time across the visible spectrum. Next, we employ liquid crystal photoalignment to geometrically phase-encode the CLCPT and integrate it into a microfluidic channel, creating planar optical devices that leverage liquid RI variations to control the optical behavior. As examples, we demonstrate on-demand tunable planar optics such as q-plates and lenses. Finally, we integrated CLCPT with an optofluidic system for dynamic color displays, thereby expanding the range of display capabilities. This dynamic CLCPT optofluidic platform represents a promising route for controlling optical fields and, when combined with large-scale microfluidic integration, has potential applications in dynamic displays, imaging, holography, and sensing.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"80 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-29DOI: 10.1021/acsphotonics.5c02900
Junhong Yu, Ke Wang, Yadong Han, Zhenzhong Lian, Songyan Hou, Chang Cao, Hilmi Volkan Demir, Jacek J. Jasieniak, Manoj Sharma
Resolving the ambiguous oxidation state of copper dopants responsible for the large Stokes-shifted emission in CdSe colloidal quantum wells (CQWs) is critical for harnessing their emerging optoelectronic properties. Employing carrier injection to tune the population distribution between Cu1+/Cu2+ centers and in situ monitoring of the copper-related emission (CE), we have revealed that the CE band undergoes blueshifting, intensity quenching, and line width broadening with gradually increased Cu2+ states. Time-resolved CE dynamics and intragap absorption further confirm that Cu2+ states generate narrow, inefficient emission with minimal Stokes shifts due to trap-mediated Auger recombination, reduced radiative center energy spanning, and Fermi-level shifts. Accordingly, we identify Cu1+ as the dominant species that produces the bright, broad CE band with its hallmark large Stokes shift. This work not only presents mechanistic clarifications but also provides an effective approach to electrically modulate defect emissions in CQWs.
{"title":"Electro-Optical Evaluation of Cu1+ and Cu2+ States in Copper-Doped CdSe Colloidal Quantum Wells","authors":"Junhong Yu, Ke Wang, Yadong Han, Zhenzhong Lian, Songyan Hou, Chang Cao, Hilmi Volkan Demir, Jacek J. Jasieniak, Manoj Sharma","doi":"10.1021/acsphotonics.5c02900","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02900","url":null,"abstract":"Resolving the ambiguous oxidation state of copper dopants responsible for the large Stokes-shifted emission in CdSe colloidal quantum wells (CQWs) is critical for harnessing their emerging optoelectronic properties. Employing carrier injection to tune the population distribution between Cu<sup>1+</sup>/Cu<sup>2+</sup> centers and in situ monitoring of the copper-related emission (CE), we have revealed that the CE band undergoes blueshifting, intensity quenching, and line width broadening with gradually increased Cu<sup>2+</sup> states. Time-resolved CE dynamics and intragap absorption further confirm that Cu<sup>2+</sup> states generate narrow, inefficient emission with minimal Stokes shifts due to trap-mediated Auger recombination, reduced radiative center energy spanning, and Fermi-level shifts. Accordingly, we identify Cu<sup>1+</sup> as the dominant species that produces the bright, broad CE band with its hallmark large Stokes shift. This work not only presents mechanistic clarifications but also provides an effective approach to electrically modulate defect emissions in CQWs.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"4 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146070529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-29DOI: 10.1021/acsphotonics.5c02627
Hang Thi Nguyet Le, Eka Lutfi Septiani, Tomoyuki Hirano, Kiet Le Anh Cao, Takashi Ogi
Photovoltaic (PV) technology has become a crucial component of the global move toward clean energy, offering a power source that is sustainable, scalable, and increasingly cost-effective. However, thermal degradation of solar cells under elevated operating temperatures remains a critical challenge. This study reports a zero-energy passive daytime radiative cooling (PDRC) approach to mitigate this issue using a high-performance transparent cooling film. The film incorporates hierarchically structured aggregated dense silica (ADS) particles embedded within a polydimethylsiloxane (PDMS) matrix, i.e., the ADS/PDMS film. ADS particles, synthesized via a spray-drying process, exhibit a distinctive porous architecture composed of nanoscale building blocks, enabling enhanced spectral selectivity. The ADS/PDMS films maintain considerable visible transparency across the crystalline-silicon absorption band to maximize power generation while achieving high near-infrared (NIR) reflection through Mie resonance and multiple scattering within the ADS architecture and exhibiting high emissivity in the 8–13 μm atmospheric transparency window. Outdoor evaluations conducted under different atmospheric conditions confirmed the reliable performance of the ADS/PDMS films, which consistently reduced operating temperatures of solar panels up to 7.5 °C on average and improved open-circuit voltages (Voc) by about 3.56%. These results demonstrate that ADS design provides an effective framework for advanced passive thermal management, contributing to enhancing the PV and long-term operational stability.
{"title":"Enhancing Passive Radiative Cooling Performance on Solar Panels via Multiple Scattering Effects in Aggregated Silica Particles/Polydimethylsiloxane Films","authors":"Hang Thi Nguyet Le, Eka Lutfi Septiani, Tomoyuki Hirano, Kiet Le Anh Cao, Takashi Ogi","doi":"10.1021/acsphotonics.5c02627","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02627","url":null,"abstract":"Photovoltaic (PV) technology has become a crucial component of the global move toward clean energy, offering a power source that is sustainable, scalable, and increasingly cost-effective. However, thermal degradation of solar cells under elevated operating temperatures remains a critical challenge. This study reports a zero-energy passive daytime radiative cooling (PDRC) approach to mitigate this issue using a high-performance transparent cooling film. The film incorporates hierarchically structured aggregated dense silica (ADS) particles embedded within a polydimethylsiloxane (PDMS) matrix, i.e., the ADS/PDMS film. ADS particles, synthesized via a spray-drying process, exhibit a distinctive porous architecture composed of nanoscale building blocks, enabling enhanced spectral selectivity. The ADS/PDMS films maintain considerable visible transparency across the crystalline-silicon absorption band to maximize power generation while achieving high near-infrared (NIR) reflection through Mie resonance and multiple scattering within the ADS architecture and exhibiting high emissivity in the 8–13 μm atmospheric transparency window. Outdoor evaluations conducted under different atmospheric conditions confirmed the reliable performance of the ADS/PDMS films, which consistently reduced operating temperatures of solar panels up to 7.5 °C on average and improved open-circuit voltages (<i>V</i><sub>oc</sub>) by about 3.56%. These results demonstrate that ADS design provides an effective framework for advanced passive thermal management, contributing to enhancing the PV and long-term operational stability.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"2 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146070528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1021/acsphotonics.5c01961
Zijie Hua, Zhao Chen, Jian Liu, Chenguang Liu
Nanoscale surface and subsurface defects in optical components act as deterministic failure sites in high-energy laser facilities, constraining operational fluence and system longevity. Nondestructive diagnostics simultaneously achieving high sensitivity for nanoscale defect detection and specificity for damage-relevant defect identification remain imperative for advancing laser resilience. We introduce dual-modal dark-field photothermal confocal microscopy enabling concurrent 3D tomography of defect geometry and absorption properties. A spatiotemporal double-filtering strategy isolates photothermal signals, enhancing signal-to-noise ratios by 7.4× over conventional photothermal imaging and 5.5× versus baseline dark-field microscopy. This sensitivity breakthrough reveals subsurface and phase defects that are inaccessible to established optical methods. Critically, the pixel-level fusion of scattering (structural) and photothermal (absorption-specific) modalities enables defect hazard grading, delivering essential specificity. By resolving the sensitivity-specificity trade-off, our approach establishes a predictive framework for laser damage resistance and preemptive mitigation in next-generation high-power optics.
{"title":"High-SNR Dark-Field Photothermal Confocal Microscopy for Multimodal Characterization of Subsurface Defects","authors":"Zijie Hua, Zhao Chen, Jian Liu, Chenguang Liu","doi":"10.1021/acsphotonics.5c01961","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c01961","url":null,"abstract":"Nanoscale surface and subsurface defects in optical components act as deterministic failure sites in high-energy laser facilities, constraining operational fluence and system longevity. Nondestructive diagnostics simultaneously achieving high sensitivity for nanoscale defect detection and specificity for damage-relevant defect identification remain imperative for advancing laser resilience. We introduce dual-modal dark-field photothermal confocal microscopy enabling concurrent 3D tomography of defect geometry and absorption properties. A spatiotemporal double-filtering strategy isolates photothermal signals, enhancing signal-to-noise ratios by 7.4× over conventional photothermal imaging and 5.5× versus baseline dark-field microscopy. This sensitivity breakthrough reveals subsurface and phase defects that are inaccessible to established optical methods. Critically, the pixel-level fusion of scattering (structural) and photothermal (absorption-specific) modalities enables defect hazard grading, delivering essential specificity. By resolving the sensitivity-specificity trade-off, our approach establishes a predictive framework for laser damage resistance and preemptive mitigation in next-generation high-power optics.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"272 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146070530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1021/acsphotonics.5c02675
Elsa Jöchl, Anna-Lydia Vieli, Lucy Hale, Felix Helmrich, Deniz Turan, Mona Jarrahi, Mattias Beck, Jérôme Faist, Giacomo Scalari
We study the electrical tunability of ultrastrong light-matter interactions between a single terahertz circuit-based complementary split ring resonator (cSRR) and a two-dimensional electron gas. For this purpose, transmission spectroscopy measurements are performed under the influence of a strong magnetic field at different set points for the electric gate bias. The resulting Landau polariton dispersion depends on the applied electric bias, as the gating technique confines the electrons in-plane down to extremely subwavelength dimensions as small as d = 410 nm. This confinement allows for the excitation of standing plasma waves at zero magnetic field and an effective tunability of the electron number coupled to the THz resonator. This allows the normalized coupling strength to be tuned in situ from η = 0.46 down to η = 0.18. This is the first demonstration of terahertz far-field spectroscopy of an electrically tunable interaction between a single terahertz resonator and electrons in a GaAs quantum well heterostructure.
{"title":"Gate-Tunable Single Terahertz Meta-Atom Ultrastrong Light-Matter Coupling","authors":"Elsa Jöchl, Anna-Lydia Vieli, Lucy Hale, Felix Helmrich, Deniz Turan, Mona Jarrahi, Mattias Beck, Jérôme Faist, Giacomo Scalari","doi":"10.1021/acsphotonics.5c02675","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02675","url":null,"abstract":"We study the electrical tunability of ultrastrong light-matter interactions between a single terahertz circuit-based complementary split ring resonator (cSRR) and a two-dimensional electron gas. For this purpose, transmission spectroscopy measurements are performed under the influence of a strong magnetic field at different set points for the electric gate bias. The resulting Landau polariton dispersion depends on the applied electric bias, as the gating technique confines the electrons in-plane down to extremely subwavelength dimensions as small as <i>d</i> = 410 nm. This confinement allows for the excitation of standing plasma waves at zero magnetic field and an effective tunability of the electron number coupled to the THz resonator. This allows the normalized coupling strength to be tuned in situ from η = 0.46 down to η = 0.18. This is the first demonstration of terahertz far-field spectroscopy of an electrically tunable interaction between a single terahertz resonator and electrons in a GaAs quantum well heterostructure.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"117 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146070532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1021/acsphotonics.5c02522
Haotian Shi, Chukun Huang, Tianheng Zhang, Youwen Zhang, Tiancheng Zheng, Changren Nie, Chuanquan Liu, Junqiang Sun
Polarization-dependent nonreciprocal behavior of integrated optical isolators plays a significant role in the functionality of photonic integrated circuits. However, conventional magneto-optic (MO) isolators based on the Faraday effect suffer from high propagation loss and fabrication complexity. Here, we demonstrate an integrated magnetic-free nonreciprocal polarization rotation device based on acousto-optic (AO) scattering, implemented on an X-cut thin-film lithium niobate (TFLN) platform. Unlike magneto- or electro-optic configurations, our device employs electrically driven surface acoustic waves to facilitate energy and momentum conversion between fundamental polarization mode pairs. By leveraging the inherent anisotropy of TFLN, efficient interpolarization conversion and large single-sideband suppression are achieved. Furthermore, a folded four-port configuration is designed to extend the AO interaction length, thereby demonstrating nonreciprocal optical propagation. The device achieves a high nonreciprocal contrast exceeding 20 dB and demonstrates a broad operational bandwidth of more than 150 GHz within the optical C band. Additionally, the optimized device exhibits a figure of merit (FoM) greater than 8 rad/dB, approximately 1 order of magnitude higher than that of state-of-the-art on-chip MO devices. These findings provide a promising route toward developing broadband nonmagnetic integrated optical isolators and enabling efficient polarization rotation or frequency conversion on other anisotropic material platforms.
{"title":"Acousto-Optic Nonreciprocal Polarization Rotation on X-Cut Thin-Film Lithium Niobate","authors":"Haotian Shi, Chukun Huang, Tianheng Zhang, Youwen Zhang, Tiancheng Zheng, Changren Nie, Chuanquan Liu, Junqiang Sun","doi":"10.1021/acsphotonics.5c02522","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02522","url":null,"abstract":"Polarization-dependent nonreciprocal behavior of integrated optical isolators plays a significant role in the functionality of photonic integrated circuits. However, conventional magneto-optic (MO) isolators based on the Faraday effect suffer from high propagation loss and fabrication complexity. Here, we demonstrate an integrated magnetic-free nonreciprocal polarization rotation device based on acousto-optic (AO) scattering, implemented on an X-cut thin-film lithium niobate (TFLN) platform. Unlike magneto- or electro-optic configurations, our device employs electrically driven surface acoustic waves to facilitate energy and momentum conversion between fundamental polarization mode pairs. By leveraging the inherent anisotropy of TFLN, efficient interpolarization conversion and large single-sideband suppression are achieved. Furthermore, a folded four-port configuration is designed to extend the AO interaction length, thereby demonstrating nonreciprocal optical propagation. The device achieves a high nonreciprocal contrast exceeding 20 dB and demonstrates a broad operational bandwidth of more than 150 GHz within the optical C band. Additionally, the optimized device exhibits a figure of merit (FoM) greater than 8 rad/dB, approximately 1 order of magnitude higher than that of state-of-the-art on-chip MO devices. These findings provide a promising route toward developing broadband nonmagnetic integrated optical isolators and enabling efficient polarization rotation or frequency conversion on other anisotropic material platforms.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"180 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146070531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ultraviolet (UV) light sources with a low power consumption are crucial for advancing integrated optoelectronics. ZnS, a wide-band-gap semiconductor with a large exciton binding energy, offers unique advantages for UV applications. However, realizing random lasing based on Mie scattering in ZnS nanowires (NWs) remains a great challenge due to material absorption loss and insufficient optical feedback. In this article, high quality ZnS NWs arrays were fabricated through an electric-field assisted high temperature sintering technique, and the random cavity was optimized by strengthening the spatial density of the randomly oriented NWs. The dominant lasing mechanism arises from free exciton B recombination, exhibiting superior optical performance with a net optical modal gain of 62 cm–1 and a high characteristic temperature of 200 K. Crucially, the room temperature lasing threshold achieves an exceptional low value of 4.87 μJ/cm2 (0.3 mW/cm2), which is 5 orders of magnitude lower compared to previous results (45.3 W/cm2), marking a significant breakthrough in excitonic laser technology. Moreover, leveraging the low spatial coherence of these ZnS random lasers, speckle-free imaging and anticounterfeiting applications have been demonstrated. This research not only quantifies the key operational parameters and significantly reduces the lasing threshold but also expands the potential applications for ZnS NW-based random lasers.
{"title":"Delocalized Random Lasing in ZnS Nanowires Via Mie Scattering","authors":"Bingheng Meng, Zhaobo Tian, Zhiyuan Ren, Shan Wang, Zhihao Huang, Puning Wang, Huan Liu, Zhipeng Wei, Longxing Su, Rui Chen","doi":"10.1021/acsphotonics.5c02504","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c02504","url":null,"abstract":"Ultraviolet (UV) light sources with a low power consumption are crucial for advancing integrated optoelectronics. ZnS, a wide-band-gap semiconductor with a large exciton binding energy, offers unique advantages for UV applications. However, realizing random lasing based on Mie scattering in ZnS nanowires (NWs) remains a great challenge due to material absorption loss and insufficient optical feedback. In this article, high quality ZnS NWs arrays were fabricated through an electric-field assisted high temperature sintering technique, and the random cavity was optimized by strengthening the spatial density of the randomly oriented NWs. The dominant lasing mechanism arises from free exciton B recombination, exhibiting superior optical performance with a net optical modal gain of 62 cm<sup>–1</sup> and a high characteristic temperature of 200 K. Crucially, the room temperature lasing threshold achieves an exceptional low value of 4.87 μJ/cm<sup>2</sup> (0.3 mW/cm<sup>2</sup>), which is 5 orders of magnitude lower compared to previous results (45.3 W/cm<sup>2</sup>), marking a significant breakthrough in excitonic laser technology. Moreover, leveraging the low spatial coherence of these ZnS random lasers, speckle-free imaging and anticounterfeiting applications have been demonstrated. This research not only quantifies the key operational parameters and significantly reduces the lasing threshold but also expands the potential applications for ZnS NW-based random lasers.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"42 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}