Article
Physics, Multidisciplinary
Julian F. Wienand, Friederike Horn, Monika Aidelsburger, Julian Bibo, Fabian Grusdt
Summary: This research demonstrates that quantized Thouless pumps connecting C-4-symmetric higher-order topological phases of matter can be described by a tuple of four Chern numbers, which measure quantized bulk charge transport in a direction-dependent manner and allows for the prediction of the sign and value of fractional corner charges. Additionally, the study reveals that the topologically nontrivial phase can be characterized by both quadrupole and dipole configurations.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Lingling Song, Huanhuan Yang, Yunshan Cao, Peng Yan
Summary: This article proposes a model of square-root higher-order Weyl semimetal (SHOWS) and experimentally confirms its existence with features of Fermi-arc surface and hinge states. The study demonstrates the realization of square-root topology in 3D solid-state platforms.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Chang-An Li, Song-Bo Zhang, Jian Li, Bjoern Trauzettel
Summary: The article introduces a three-dimensional interferometer based on second-order topological insulators, which can control the interference pattern of the conductance by changing the direction of the magnetic field, showing a characteristic beating pattern with multiple frequencies.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Leena Aggarwal, Penghao Zhu, Taylor L. Hughes, Vidya Madhavan
Summary: Experimental studies reveal that Bi and BiSb alloys on (110) facets exhibit localized hinge states, establishing them as higher order topological insulators (HOTIs).
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Hui Chen, Hongkuan Zhang, Qian Wu, Yu Huang, Huy Nguyen, Emil Prodan, Xiaoming Zhou, Guoliang Huang
Summary: The authors demonstrate 1D and 2D dynamic topological pumping in acoustic crystals with cavity arrays strongly coupled through modulated channels, showing the robustness of higher-order topological sound transport against geometrical imperfections.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Christian Schweikert, Anastasia Tsianaka, Niklas Hoppe, Rouven H. Klenk, Raik Elster, Markus Greul, Mathias Kaschel, Alexander Southan, Wolfgang Vogel, Manfred Berroth
Summary: A compact integrated and high-efficiency polarization mode interferometer is presented in the 220-nm silicon-on-insulator platform. By operating with two polarization modes in a single waveguide, it achieves low propagation losses, high sensitivities, and a small footprint. The designed and fabricated system with a 5-mm-long sensing region demonstrates a measured excess loss of only 1.5 dB and an extinction ratio up to 30dB. The simulated homogeneous bulk sensitivity exceeds 8000 rad/RIU. When combined with a 90 hybrid readout system, it enables single wavelength operation with unambiguousness for phase shifts up to 2 pi and constant sensitivity.
Article
Multidisciplinary Sciences
Xiujuan Zhang, Yuan Tian, Jian-Hua Jiang, Ming-Hui Lu, Yan-Feng Chen
Summary: The study demonstrates the higher-order non-Hermitian skin effect in two-dimensional acoustic higher-order topological insulators, where non-Hermiticity drives wave localizations toward opposite edges upon different spin polarizations. Additionally, for finite systems with both edges and corners, the higher-order non-Hermitian skin effect leads to wave localizations toward two opposite corners in a spin-dependent manner, allowing for rich wave manipulation.
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Deyuan Zou, Tian Chen, Wenjing He, Jiacheng Bao, Ching Hua Lee, Houjun Sun, Xiangdong Zhang
Summary: This work reports the experimental realizations of hybrid higher-order skin-topological effect in non-reciprocal topoelectrical circuits, showcasing the dynamic interplay of non-reciprocal pumping and topological localization to form various states. Through a highly versatile and scalable circuit platform, the authors demonstrate higher-order topological skin effects, paving the way for applications in topological switching and sensing.
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
He Gao, Haoran Xue, Zhongming Gu, Tuo Liu, Jie Zhu, Baile Zhang
Summary: The study discusses the impact of introducing losses on higher-order topological insulators in an acoustic crystal, demonstrating that losses with non-Hermitian properties can induce the emergence of higher-order topology, paving the way for exploring exotic non-Hermitian-induced topological phases.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Shiqiao Wu, Bin Jiang, Yang Liu, Jian-Hua Jiang
Summary: The researchers proposed an all-dielectric PhC with unconventional higher-order band topology, which includes fractional charge effects. They demonstrated that this effect can be verified through the local density-of-states of photons, and introduced the emergence of localized states and fractional spectral charges around a disclination in the topological PhC.
PHOTONICS RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Minwoo Jung, Yang Yu, Gennady Shvets
Summary: Our study demonstrates that the presence of a localized state at the corner of an insulating domain is not always related to a certain nontrivial higher-order topological invariant, despite appearing in the same Hamiltonian parameter space. Topological corner states may not be correlated with other well-established higher-order boundary observables, motivating further development for associating corner state existence with the higher-order topology of host materials.
Article
Optics
Yin Xu, Luping Liu, Xin Hu, Yue Dong, Bo Zhang, Yi Ni
Summary: This study proposes a scalable silicon-based mode-order conversion scheme that can efficiently convert the mode-order from fundamental TE mode to various higher-order TE modes in a short conversion length. The proposed scheme achieves high mode conversion efficiency, wide working bandwidths, and detailed fabrication tolerances.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Optics
Yu Qu, Lei Lei, Yu Yu, Xinliang Zhang, Ping Xu, Zhengfang Qian
Summary: In this paper, a new design of grating couplers (GCs) is proposed to overcome the limited optical bandwidth of traditional GCs caused by the wavelength's dependency on the coupling angle. This device combines a dual-broadband achromatic metalens (ML) with two focusing GCs to achieve excellent dual-broadband achromatic convergence. The ML-assisted GCs device exhibits a good broadband property, improving the coupling of spatial light with a wide spectrum.
Article
Physics, Multidisciplinary
Rui Chen, Tianyu Liu, C. M. Wang, Hai-Zhou Lu, X. C. Xie
Summary: The paper discusses the Fermi-arc mechanism of the 3D quantum Hall effect in Weyl semimetals and proposes a method to achieve one-sided hinge states in Cd3As2-like Dirac semimetals using a tilted magnetic field. Additionally, a new experimental approach to detect these one-sided hinge states is suggested.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Xu Han, Li Chen, Yongheng Jiang, Andreas Frigg, Huifu Xiao, Thach Giang Nguyen, Andreas Boes, Jianhong Yang, Guanghui Ren, Yikai Su, Arnan Mitchell, Yonghui Tian
Summary: This paper proposes and demonstrates compact subwavelength grating (SWG) waveguides on an LNOI platform for on-chip mode and polarization manipulation. The SWGs, designed and formed on a silicon nitride thin film, show low insertion losses and high extinction ratio, making them promising building blocks for integrated photonics applications.
LASER & PHOTONICS REVIEWS
(2022)
Article
Engineering, Electrical & Electronic
Peicheng Liao, Changjing Bao, Ahmed Almaiman, Arne Kordts, Maxim Karpov, Martin Hubert Peter Pfeiffer, Lin Zhang, Fatemeh Alishahi, Yinwen Cao, Kaiheng Zou, Ahmad Fallahpour, Ari N. Willner, Moshe Tur, Tobias J. Kippenberg, Alan E. Willner
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2019)
Article
Engineering, Electrical & Electronic
Yuanhang Zhang, Mohammed A. Al-Mumin, Huiyuan Liu, Chi Xu, Lin Zhang, Patrick L. LiKamWa, Guifang Li
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2019)
Article
Engineering, Electrical & Electronic
Lijuan Xu, Minghui Yang, Yuhao Guo, Henan Liu, Guifang Li, Lin Zhang
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2019)
Article
Engineering, Electrical & Electronic
Yuxi Fang, Changjing Bao, Zhi Wang, Bo Liu, Lin Zhang, Xu Han, Yuxuan He, Hao Huang, Yongxiong Ren, Zhongqi Pan, Yang Yue
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2020)
Article
Engineering, Electrical & Electronic
Xin Tong, Henan Liu, Guifang Li, Lin Zhang
Summary: The study introduces an integrated waveguide optical tweezer design that achieves focusing of upward radiation through etched trenches on a waveguide. Optimization of the antenna's structural parameters generates a quasi-Gaussian field distribution above the antenna. The gradient distribution of the electric field produces gradient force, enabling effective optical trapping of microscale particles.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Xin Tong, Hao Tian, Yongjun Guo, Meng Zhang, Lin Zhang
Summary: The study introduces a method of integrating nanophotonic traps in a microfluidic channel, utilizing a slot waveguide and nano-slit to generate strong optical forces for trapping nanoparticles, forming a large array of optical traps expected for application in biological nanoparticle research.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Yaping Liu, Yongmin Jung, Zhiqun Yang, Lin Zhang, David J. Richardson
Summary: A new type of all-fiber mode scrambler is proposed for mode division multiplexed data transmission based on few mode fibers, achieving low loss and wideband mode coupling by randomly placing multiple point-loads along the fiber length. An exemplar experimental demonstration with 150 randomly located point-loads in step-index two mode fibers shows uniform mode coupling over the C band with an insertion loss of less than 1 dB.
IEEE PHOTONICS JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Zhongjing Hu, Lijuan Xu, Jing Wang, Yuke Zhai, Lin Zhang
Summary: This study demonstrated supercontinuum generation in a dispersion-engineered silicon nitride waveguide pumped with 10ps pulses at 1550 nm wavelength, resulting in a spectrum from 656 to 3867 nm with power variation <15 dB and a very flat pedestal with <5 dB variation. The research highlights the unique role of dispersion tailoring in achieving a broad and flat supercontinuum generation, making it highly desirable for various applications.
IEEE JOURNAL OF QUANTUM ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Zhi Cheng, Xin Tong, Lin Zhang
Summary: Near-field optical tweezers integrated on a chip are gaining attention for biological and chemical analyses. A low-loss Si waveguide with a high intensity gradient in the electric field is proposed for trapping microparticles. The device has high transmittance and the ability to analyze optical forces in all three dimensions.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Weicheng Chen, Rongxiang Guo, Dian Wan, Tarun Sharma, Lin Zhang, Tiegen Liu, Zhenzhou Cheng
Summary: On-chip Kerr frequency combs provide unprecedented opportunities for optical communications and optical interconnects with compact, low-cost, and high-density wavelength-division multiplexing (WDM) techniques. A dual-mode Kerr frequency comb based on a graphene-on-silicon (GOS) microring is proposed to overcome the limitation of traditional approaches and achieve high-speed optical communications.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Xiushan Du, Yuke Zhai, Leonardo Midolo, Lin Zhang, Xiaoyan Zhou
Summary: This paper proposes a method for efficient frequency conversion using a nanomechanical silicon-rich nitride waveguide device, to address the frequency conversion challenge in on-demand single-photon sources. Numerical results show that optimal conversion efficiency over 99% and high signal-to-noise ratio can be achieved when the waveguide loss is negligible.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Wenpu Geng, Yuxi Fang, Yingning Wang, Zhi Wang, Yan-ge Liu, Lin Zhang, Changjing Bao, Yongxiong Ren, Zhongqi Pan, Yang Yue
Summary: In this study, a dual concentric-ring-core fiber design was proposed to achieve near-zero and flat dispersion profiles over a 3007-nm wavelength range with four zero-dispersion wavelengths for the OAM mode. The precise position of the zero-dispersion wavelengths can be tailored by varying the structural variables and the germanium-doped concentration of the silica-based fiber. Simulation results showed that by pumping a 50-fs 600-kW Gaussian pulse at the central wavelength of 1900 nm into a 2-mm designed fiber, the OAM(3,1) mode supercontinuum spectrum can achieve beyond three-octave spanning from 445 to 3942 nm at -40 dB level. By further optimizing the proposed fiber structure for the OAM(1,1) mode with <60 ps/(nm.km) dispersion variation over a 3210-nm bandwidth, the generated supercontinuum can cover nearly three octaves.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Optics
Rui Duan, Yi Tian Thung, Zitong Zhang, Emek Goksu Durmusoglu, Yichen He, Lian Xiao, Calvin Xiu Xian Lee, Wen Siang Lew, Lin Zhang, Hanyang Li, Jun Yang, Hilmi Volkan Demir, Handong Sun
Summary: Soft matter-based microlasers, with their flexibility and functional network topology, are considered as excellent building blocks for photonic interconnected networks. However, challenges like poor lasing stability and high lasing threshold hinder their potential. In this study, a high-quality, low-threshold nanoplatelets-based polymer microfiber laser and its photonic interconnected networks are successfully demonstrated. The work pioneers the exploration of polygonal self-coupling microlasers and provides insights for unit design and programming in future photonic network systems.
LASER & PHOTONICS REVIEWS
(2023)
Article
Computer Science, Information Systems
Lijuan Xu, Yuhao Guo, Jing Wang, Zhaohong Han, Henan Liu, Jurgen Michel, Lionel C. Kimerling, Lin Zhang
Summary: This paper proposes a new type of athermal waveguide composed of TiO2 with a negative TOC and SiC with a positive TOC, which maintains near-zero TOC over a broad bandwidth and low anomalous dispersion. The waveguide structure is suitable for microresonators and can be bent tightly without experiencing significant losses.
Article
Computer Science, Information Systems
Yuxi Fang, Changjing Bao, Zhi Wang, Yange Liu, Lin Zhang, Si-Ao Li, Yiwen Zhang, Hao Huang, Yongxiong Ren, Zhongqi Pan, Yang Yue
