Article
Materials Science, Multidisciplinary
R. P. Day, I. S. Elfimov, A. Damascelli
Summary: The issue of surface sensitivity and its relationship with the interpretation of spectral features observed in angle-resolved photoemission spectroscopy experiments is explored in this study. By investigating a vacuum-terminated crystalline slab, we find a consistent connection between reliable kz fidelity and the acute surface sensitivity of this technique. Furthermore, we identify several critical issues that affect the estimation of kF, band velocity, and self-energy from photoemission experiments.
Article
Nanoscience & Nanotechnology
Pengfei Cheng, Honglei Wang, Bjoern Mueller, Jens Mueller, Dong Wang, Peter Schaaf
Summary: Research has focused on efficiently harvesting solar energy with black silicon (b-Si), where highly conductive b-Si prepared by reactive ion etching can absorb a wide range of wavelengths and convert solar energy into electric power. The optimized b-Si shows low reflection rates and great potential for photothermal applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Tamara E. E. Czerny, Qian Shen, Jochen Konieczny, Martin A. A. Schroer, Markus Winterer, Franziska Muckel
Summary: This study reports on filter-less color-selective photoconductivity in 2D perovskite thin film devices, exhibiting a distinct resonance in the photocurrent spectrum that correlates to excitonic absorption. The devices show efficient charge carrier separation and achieve an external quantum efficiency of <=8.9% at the excitonic peak, with response times of 150 μs and a maximum specific detectivity of 2.5 × 10(10) Jones.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Zhiang Zhang, Jikun Jiang, Xiao (Xiao) Liu, Xin Wang, Luyao Wang, Yuankun Qiu, Zhanfei Zhang, Yiting Zheng, Xueyun Wu, Jianghu Liang, Congcong Tian, Chun-Chao Chen
Summary: This study demonstrated that anchoring acetylcholine (ACh(+)) on the surface of a quadruple-cation perovskite can improve band alignment, minimize V-oc loss, and passivate defects, resulting in efficient and stable perovskite solar cells. The ACh(+) treatment significantly enhanced power conversion efficiency (PCE) and open-circuit voltage (V-oc) while reducing hysteresis index, making it a promising strategy for PSCs preparation.
Article
Optics
Weijia Shao, Weihao Cui, Junhui Hu, Yongmei Wang, Jian Tang, Xiaofeng Li
Summary: We designed a planar hot-electron photodetector with polarity-switchable photocurrent controlled by the working wavelength. By altering the wavelength, the photocurrent polarity of the device can be switched, providing a new approach for flexible hot-electron photodetection.
Article
Materials Science, Multidisciplinary
Dae-Kyoung Kim, Seok-Bo Hong, Jonghoon Kim, Mann-Ho Cho
Summary: The research revealed that the Bi2Se3/BP heterostructure exhibits high-efficiency photocharacteristics due to its narrow band gap and high mobility of the Dirac surface state. Furthermore, the heterostructure can form heterojunctions in the sharp interface region, resulting in a strong built-in electric field and contribution to photoexcited carrier tunneling through the interactive interfacial region.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Andrey M. Tokmachev, Dmitry Averyanov, Alexander N. Taldenkov, Ivan S. Sokolov, Igor A. Karateev, Oleg E. Parfenov, Vyacheslav G. Storchak
Summary: Sub-monolayer superstructures of Eu atoms self-assembled on the silicon surface exhibit strong magnetic signals, revealing robust easy-plane magnetism in both one- and two-dimensionally ordered structures. This emergence of 2D magnetism shows a strong dependence of the effective transition temperature on weak magnetic fields, providing a versatile platform for miniaturization of 2D magnetic systems for applications in information technologies.
Article
Physics, Multidisciplinary
Lihong Zhou, Haowei Li, Wei Yi, Xiaoling Cui
Summary: The authors propose a scheme to achieve topological non-Hermitian skin effect in ultracold gases, where the strength of the spin orbit coupling is tuned to realize a non-trivial band topology.
COMMUNICATIONS PHYSICS
(2022)
Article
Physics, Multidisciplinary
K. A. Matveev
Summary: We investigate momentum-resolved tunneling into a system of spinless chiral one-dimensional fermions, such as electrons at the edge of an integer quantum Hall system. Interactions between particles cause broadening of the system's spectral function. We develop an approach that allows us to obtain the shape of the peak in the spectral function in the regime of strong interaction. We apply this technique to the cases of short-range and Coulomb interactions.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
V. N. Strocov, L. L. Lev, F. Alarab, P. Constantinou, X. Wang, T. Schmitt, T. J. Z. Stock, L. Nicolai, J. Ocenasek, J. Minar
Summary: A three-dimensional electronic band structure is crucial for understanding various physical phenomena in solid-state systems. Researchers have discovered that even at high excitation energies, the final states in materials like silver can be more complex than initially thought, incorporating multiple Bloch waves with different momenta. This complexity leads to broadening of spectral peaks and a complex structure in the photoemission data. These findings are important for accurately determining the 3D band structure in a wide range of materials and excitation energies in angular-resolved photoemission experiments.
NATURE COMMUNICATIONS
(2023)
Article
Optics
Matteo Secli, Tomoki Ozawa, Massimo Capone, Iacopo Carusotto
Summary: In this study, a semiclassical theory of laser oscillation in a chiral edge state of a topological photonic system with frequency-dependent gain is developed. By considering a Harper-Hofstadter lattice embedding two-level atoms as a gain material, the researchers demonstrate a flexible mode-selection mechanism that can stabilize single-mode lasing into an edge state. The implications of these results for recent experiments are outlined.
Article
Optics
Yi-Han He, Yong-Feng Gao, Yue He, Xiao-Fei Qi, Jing-Qi Si, Ming Yang, Shu-Yang Zhou
Summary: In this paper, a two-dimensional all-dielectric PCs platform with kagome lattices is utilized to realize topological edge states in different frequency bands, and to achieve dual-band single channel waveguide and frequency divider. Furthermore, the origins of the two types of corner states in combined triangle and parallelogram box-shaped structures are investigated, enhancing the localized energy intensity in the PCs platform. These works have significant potential for application in integrated nanophotonic devices.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Chia-Hung Wu, Chih-Jen Ku, Min-Wen Yu, Jhen-Hong Yang, Tien-Chang Lu, Tzy-Rong Lin, Chan-Shan Yang, Kuo-Ping Chen
Summary: Recently, there has been significant research on nanoscale light manipulation using surface plasmon polaritons (SPPs). This study investigates the light-matter interaction between graphene and SPPs, and proposes a non-scattering detection method by integrating single-layer graphene into asymmetric SPP nanoantenna arrays. The developed device shows a high photoresponsivity of 15 mA/W, which holds promise for on-chip optical communication in the future.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Dmitry Ovchinnikov, Xiong Huang, Zhong Lin, Zaiyao Fei, Jiaqi Cai, Tiancheng Song, Minhao He, Qianni Jiang, Chong Wang, Hao Li, Yayu Wang, Yang Wu, Di Xiao, Jiun-Haw Chu, Jiaqiang Yan, Cui-Zu Chang, Yong-Tao Cui, Xiaodong Xu
Summary: MnBi2Te4 is a van der Waals magnet that can form a Chern insulator when all spins are aligned by an applied magnetic field. Through in-depth investigation, it is found that the bulk electronic structure evolves as the magnetic state is tuned, with a one-to-one correspondence with layer thickness, topological order, and magnetic state. Additionally, band topology and magnetic order in this newly discovered topological magnet exhibit an interplay during the continuous tuning of the magnetic state.
Article
Materials Science, Multidisciplinary
Andrea Benfenati, Egor Babaev
Summary: In this study, we investigate the microscopic model of a frustrated s-wave superconductor with interband interaction. We find that the strong frustration leads to an s + is state, which breaks the time reversal symmetry of the s-wave superconductor. Additionally, we identify another phase where the bulk of the system is in a conventional s-wave state, but the superconducting surface states break the time reversal symmetry. Moreover, we show that s + is superconductors can exhibit spontaneous boundary currents and magnetic fields at lower-dimensional boundaries, specifically at the corners of two-dimensional samples. These results demonstrate that boundary current effects in superconductors can arise in states that are not topological or chiral according to the modern classification.
