Article
Optics
Lechen Yang, Guangrui Li, Xiaomei Gao, Ling Lu
Summary: Output power and beam quality are the main limitations for semiconductor lasers. The use of Dirac-vortex topological cavity overcomes the difficulty of single-mode selection and achieves excellent performance. These lasers can be used at important wavelengths for communication and safety, and also have the capability for multiple wavelengths, making them highly versatile.
Article
Physics, Multidisciplinary
Jongjun M. Lee, Myung-Joong Hwang, Hyun-Woo Lee
Summary: The study investigates the possibility of combining cavity magnonics and topological insulators by exploring hybrid cavity systems incorporating a ferromagnet and a topological insulator. The researchers find that the topological surface state efficiently mediates the coupling between the spin of the ferromagnet and the electric field of the cavity, which is different from the conventional magnetic dipole coupling. They refer to this coupling as topological magnon-photon interaction and show that it is significantly stronger than the conventional magnon-photon coupling. The proposed device has the potential to scale down and control the cavity system using electronics.
COMMUNICATIONS PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Nusrat Jahan, Kent D. Choquette
Summary: We demonstrate in simulation and experiment the tunability of the coherent coupling of electric fields between elements of a triangular photonic crystal vertical cavity surface emitting laser (VCSEL) array to form antiguided supermodes. By adjusting the injection currents into each array element, the array can emit in a desired supermode. The power confined within the central portion of the in-phase coupled beam is higher than that emitted from a single VCSEL, which is beneficial for high-brightness applications.
IEEE PHOTONICS JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Petr N. N. Kim, Dmitry P. P. Fedchenko, Natalya V. V. Rudakova, Ivan V. V. Timofeev
Summary: This study proposes a tiling photonic topological insulator constructed from connected prism resonators, which has a topologically-protected propagating state due to the disconnected faces of the edge resonators. The structure exhibits robustness against structural defects and scalability in wavelength and resonator size. The tiling is suggested for active topological photonic devices and laser arrays.
APPLIED SCIENCES-BASEL
(2023)
Article
Optics
Xianglian Liu, Lijiao Zhao, Di Zhang, Shaohua Gao
Summary: Researchers have proposed a topological cavity laser based on valley photonic crystals, utilizing topological edge states to design a cavity with high-quality factors, serving as an ultra-small light source. This laser can suppress backscattering and is immune to defects and disorders.
Article
Multidisciplinary Sciences
A. Schumer, Y. G. N. Liu, J. Leshin, L. Ding, Y. Alahmadi, A. U. Hassan, H. Nasari, S. Rotter, D. N. Christodoulides, P. LiKamWa, M. Khajavikhan
Summary: Shaping the light emission characteristics of laser systems is crucial in various fields. By designing a specific structure, researchers demonstrate how to form a pair of orthogonal states in a laser cavity, which can be utilized for developing versatile mode-selective devices and exploring the topological features of exceptional points.
Article
Optics
Amit Pando, Sagie Gadasi, Asher Friesem, Nir Davidson
Summary: We propose an intra-cavity adaptive optics method to reduce the frequency spread and improve phase locking of coupled lasers. By using a spatial light modulator and an iterative optimization algorithm, we achieve a fourfold enhancement in phase locking of 450 coupled lasers, as measured by the peak intensity and the inverse participation ratio of the far-field output distributions. We also demonstrate that this improvement is long-lasting and suitable for phase locking of weakly coupled lasers.
Article
Engineering, Electrical & Electronic
Nusrat Jahan, Katherine A. Lakomy, Pawel Strzebonski, B. J. Thompson, K. D. Choquette
Summary: This study reports a method to reduce beam divergence from coherently-coupled ring arrays of photonic crystal VCSELs and provides experimental verification. The method relies on photonic crystal etching and independent current injection to achieve optically coupled array elements and reduce the beam divergence angle.
IEEE PHOTONICS JOURNAL
(2022)
Article
Physics, Multidisciplinary
Ashley M. Cook, Joel E. Moore
Summary: This article uncovers a new class of multiplicative topological phases using symmetry, which have nontrivial topological properties and can carry current at the edges of the sample. Considerable understanding of these phases has been gained recently by considering additional protecting symmetries, different types of quasiparticles, and systems out of equilibrium. The authors construct a large class of previously unidentified multiplicative topological phases characterized by tensor product Hilbert spaces, and demonstrate their methods by introducing multiplicative topological phases based on Hopf and Chern insulator phases.
COMMUNICATIONS PHYSICS
(2022)
Article
Quantum Science & Technology
Kashif Ammar Yasir, Lin Zhuang, Wu-Ming Liu
Summary: We investigate topological nonlinear optics with spin-orbit coupled Bose-Einstein condensate in a cavity and demonstrate different types of optical transparencies and the formation of topological edge states through quantum interference. These findings are significant for topological photonics and their application in quantum computation.
NPJ QUANTUM INFORMATION
(2022)
Article
Materials Science, Multidisciplinary
Toshihiro Sato, Martin Hohenadler, Tarun Grover, John McGreevy, Fakher F. Assaad
Summary: （English Summary:）
In the system of Dirac fermions in (2 + 1) dimensions with dynamically generated anticommuting SO(3) antiferromagnetic and Z(2) Kekule valence-bond solid (KVBS) masses, there exists a field theory with a topological theta term that allows for continuous phase transitions. The presence of topological defects and the theta term play crucial roles in the transition process in this system.
Article
Materials Science, Multidisciplinary
Xiao-Chen Sun, Xiao Hu
Summary: Theoretical analysis shows that topological ring-cavity (TRC) modes can be used for stable single-mode lasing, with significantly higher intensity compared to other modes. By injecting circularly polarized beams, specific TRC modes with desired orbital angular momentum can be selectively stimulated. Advanced semiconductor nanotechnologies can be utilized to fabricate topological lasers generating chiral laser beams ideal for novel photonic functions.
Article
Chemistry, Multidisciplinary
Yibo Dong, Guanzhong Pan, Meng Xun, Hang Su, Long Chen, Yun Sun, Haitao Luan, Xinyuan Fang, Dexin Wu, Min Gu
Summary: By integrating a nanoprinted OAM phase structure on VCSELs, we successfully demonstrated a vortex microlaser with a low threshold and simple structure. A monolithic microlaser array with addressable control of vortex beams was achieved. Nanoprinting and spiral phase plate design were used to obtain high-purity vortex beams.
Article
Multidisciplinary Sciences
Yuqi Liu, Weidong Cao, Weijian Chen, Hua Wang, Lan Yang, Xuan Zhang
Summary: Topological insulators (TIs) have been widely studied in photonics and acoustics due to their unique physical properties and potential applications. This article explores TIs on an integrated circuit (IC) platform and designs a fully integrated topological circuit chain. Through comprehensive post-layout simulations, the researchers observe and evaluate the characteristics of the topological circuit. The results demonstrate the feasibility and promise of large-scale topological electronics research with IC technology.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Multidisciplinary
Hao-Ke Xu, Mingqiang Gu, Fucong Fei, Yi-Sheng Gu, Dang Liu, Qiao-Yan Yu, Sha-Sha Xue, Xu-Hui Ning, Bo Chen, Hangkai Xie, Zhen Zhu, Dandan Guan, Shiyong Wang, Yaoyi Li, Canhua Liu, Qihang Liu, Fengqi Song, Hao Zheng, Jinfeng Jia
Summary: Research has discovered that MnBi4Te7 is a topological insulator with quantum anomalous Hall effect and axion insulator phase. Through scanning tunneling spectroscopy, it has been observed that there is an electronic state at the edge of the magnetic MnBi2Te4 layer at 4.5 K, but not in the nonmagnetic Bi2Te3 layer. As the temperature increases, the edge state disappears, while the state induced by point defects persists.
Editorial Material
Physics, Applied
Christoph Becher, Sven Hoefling, Jin Liu, Peter Michler, Wolfram Pernice, Costanza Toninelli
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Jiaqi Hu, Nathanial Lydick, Zhaorong Wang, F. Jabeen, C. Schneider, Sven Hoefling, Hui Deng, Hui Deng
Summary: Exciton-polaritons have become a promising platform for non-Hermitian physics. This article presents an experimental method using microcavities with sub-wavelength gratings as reflectors to control the energy and linewidth of polariton modes.
APPLIED PHYSICS LETTERS
(2022)
Article
Optics
Josephine Nauschuetz, Hedwig Knoetig, Robert Weih, Julian Scheuermann, Johannes Koeth, Sven Hoefling, Benedikt Schwarz
Summary: This article presents GaSb-based interband cascade lasers (ICLs) operating at a center wavelength of 6.12 μm in continuous-wave mode up to a maximum temperature of 40 °C. The performance of the devices is improved by adjusting the Ga1-xInxSb layer thickness in the active region to reduce valence intersubband absorption. The optimization of the device design and electron injector rebalances the electron and hole concentrations, resulting in low threshold current densities and power consumption, making them suitable for mobile and compact sensing systems.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Jonathan Jurkat, Sebastian Klembt, Marco De Gregorio, Moritz Meinecke, Quirin Buchinger, Tristan H. Harder, Johannes Beierlein, Oleg A. Egorov, Monika Emmerling, Constantin Krause, Christian Schneider, Tobias Huber-Loyola, Sven Hoefling
Summary: The introduction of topological physics to photonics has resulted in the development of robust photonic devices. While classical topological protection of light has been achieved, the utilization of quantum light sources in devices with topologically nontrivial resonances remains largely unexplored.
Review
Optics
Soham Saha, Ohad Segal, Colton Fruhling, Eran Lustig, Mordecai Segev, Alexandra Boltasseva, Vladimir M. Shalaev
Summary: Recent advances in ultrafast, large-modulation photonic materials have led to the potential development of photonic time crystals. This perspective discusses the promising candidates for photonic time crystals, outlining their modulation speed and depth. The challenges and possible paths to success are also analyzed.
Article
Engineering, Electrical & Electronic
Nikolai B. Chichkov, Amit Yadav, Franck Joulain, Solenn Cozic, Semyon V. Smirnov, Leon Shterengas, Julian Scheuermann, Robert Weih, Johannes Koeth, Sven Hofling, Ulf Hinze, Samuel Poulain, Edik U. Rafailov
Summary: Building upon recent advances in GaSb-based diode lasers and Er-doped fluoride fibre technologies, this article demonstrates the fibre-based amplification of mid infrared diode lasers around 2.78 μm for the first time. The experimental results show output powers up to 0.9 W, pulse durations as short as 20 ns, and pulse repetition rates up to 1 MHz. Additionally, the impact of different fibre end-cap materials on laser performance is analyzed.
IEEE PHOTONICS JOURNAL
(2023)
Article
Materials Science, Multidisciplinary
Michael D. Fraser, H. Hoe Tan, Yago del Valle Inclan Redondo, Hima Kavuri, Elena A. Ostrovskaya, Christian Schneider, Sven Hoefling, Yoshihisa Yamamoto, Seigo Tarucha
Summary: The use of high energy proton implantation allows for precise and independent manipulation of both exciton and photon energies in GaAs microcavity exciton-polaritons. This technique involves post-growth proton implantation and annealing steps to induce small local interdiffusion, resulting in energy shifts in exciton or photon components. The polariton mode can be tuned by more than 10 meV, altering the effective mass for photon and exciton energy shifts, while maintaining narrow-linewidth polariton emission and condensation.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Physics, Applied
Quirin Buchinger, Simon Betzold, Sven Hoefling, Tobias Huber-Loyola
Summary: We conducted an optical study on various device designs of electrically contactable circular Bragg grating cavities in labyrinth geometries. In order to establish an electrical connection between the central disk and the surrounding membrane, we introduced connections between the adjacent rings separated by air gaps. By rotating these connections to create a labyrinth-like structure, we improved mode confinement, far-field pattern, and Purcell factor compared to layouts with connections arranged in straight lines. Reflectivity measurements and simulations were conducted to investigate the effects of different arrangements and sizes of connections on the optical properties and to determine the optimal design.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yago del Valle-Inclan Redondo, Christian Schneider, Sebastian Klembt, Sven Hoefling, Seigo Tarucha, Michael D. Fraser
Summary: We have created a rotating polariton condensate at gigahertz frequencies by off-resonantly pumping with a rotating optical stirrer composed of structured laser modes. The results show that the rotating polariton condensate acquires angular momentum exceeding the critical 1n/particle and demonstrates deterministic nucleation and capture of quantized vortices with a handedness controlled by the pump rotation direction. This study enables new opportunities for exploring open dissipative superfluidity, ordering of non-Hermitian quantized vortex matter, and topological states in a highly nonlinear, photonic platform.
Article
Physics, Multidisciplinary
Carolin Lueders, Matthias Pukrop, Franziska Barkhausen, Elena Rozas, Christian Schneider, Sven Hoefling, Jan Sperling, Stefan Schumacher, Marc Assmann
Summary: We have developed a novel phase-space method to dynamically monitor quantum coherence in polariton condensates. Our approach allows us to quantify complex decoherence mechanisms and provides a stable system for long-term coherence. By reconstructing phase-space functions from homodyne detection data, we have demonstrated the potential of using quantum coherence for information processing up to the nanosecond regime.
PHYSICAL REVIEW LETTERS
(2023)
Article
Environmental Sciences
Sergio J. Goncalves Jr, Heitor Evangelista, Johannes Weis, Tristan H. Harder, Swarup China, Simon Mueller, Magdalena M. Marques, Newton de Magalhaes Neto, Heber R. Passos, Marcelo Sampaio, Jefferson C. Simoes, Bruno Vinicius Ximenes de Oliveira, Carlos I. Yamamoto, Alexander Laskin, Mary K. Gilles, Ricardo H. M. Godoi
Summary: Since the 1980s, researchers have been using the Antarctic environment as a natural laboratory to study the effects of stratospheric ozone depletion on increased ultraviolet radiation levels. However, there are still gaps in our understanding. New evidence shows that increased ultraviolet radiation is impacting sea salt aerosols in West Antarctica, which play a crucial role in the Earth's radiative balance. Molecular analysis reveals abundant chlorine-enriched aerosols in sea salt, generated by photolytic products, while ice core records suggest increasing chlorine depletion since the onset of ozone depletion in the stratosphere.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Optics
Urban Senica, Alexander Dikopoltsev, Andres Forrer, Sara Cibella, Guido Torrioli, Mattias Beck, Jerome Faist, Giacomo Scalari
Summary: This study demonstrates the generation of self-starting frequency-modulated combs by enhancing the gain saturation dynamics and nonlinearities through spatial modulation in semiconductor lasers. Using terahertz quantum cascade lasers and taking advantage of spatial confinement, pure frequency-modulated combs with flat intensity spectra and clear linear frequency chirps can be generated.
LASER & PHOTONICS REVIEWS
(2023)
Editorial Material
Optics
Dali Cheng, Eran Lustig, Kai Wang, Shanhui Fan
Summary: The concept of synthetic dimensions in photonics provides a versatile platform in exploring multi-dimensional physics. We propose and experimentally demonstrate a method to fully measure multi-dimensional band structures in the synthetic frequency dimension. By introducing a gauge potential into the lattice Hamiltonian, we can measure the band structure of the lattice over the entire multi-dimensional Brillouin zone. Our results reveal the properties of point-gap topology of non-Hermitian Hamiltonian in more than one dimensions.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Review
Physics, Applied
Alexey Kavokin, Timothy C. H. Liew, Christian Schneider, Pavlos G. Lagoudakis, Sebastian Klembt, Sven Hoefling
Summary: Polariton lasers emit coherent monochromatic light through a spontaneous emission process and show properties of Bose-Einstein condensation and superfluidity at room temperature. Emerging material systems for polariton lasers include organic molecules, transition metal dichalcogenides, perovskites, and liquid-crystal microcavities, which have potential applications in topological lasing, classical neuromorphic computing, and quantum information processing. Polaritonics, the study of strongly coupled light-matter states, offers advantages in classical and quantum information processing with full optical control and read-out capabilities.
NATURE REVIEWS PHYSICS
(2022)
