Article
Chemistry, Multidisciplinary
Andrew M. Boyce, Jon W. Stewart, Jason Avila, Qixin Shen, Siyuan Zhang, Virginia D. Wheeler, Maiken H. Mikkelsen
Summary: Sub-10-nm-thick VO2 films deposited by atomic layer deposition (ALD) are integrated with plasmonic nanogap cavities to demonstrate tunable, spectrally selective absorption in the near-infrared (NIR) region. The absorption resonance can be blue-shifted by up to 60 nm upon inducing the phase transition via heating, and this process is reversible and repeatable over multiple temperature cycles.
Article
Engineering, Electrical & Electronic
Chang Shu, Chen Zhang, Yulong Ye, Tongqing Lin
Summary: A tunable toroidal resonance generated in a hybrid metal-vanadium dioxide metamaterial is proposed and analyzed in this paper. The simulation results show that the toroidal resonance is generated by co-exciting two reversed closed-loop poloidal currents. It is found that the toroidal resonance is insensitive to the polarization angle due to the symmetrical structure. Additionally, the amplitude of the toroidal resonance can be actively tuned by varying the conductivity of VO2.
JOURNAL OF ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Xian-Xin Wu, Wen-Yu Jiang, Xiao-Feng Wang, Li-Yun Zhao, Jia Shi, Shuai Zhang, Xinyu Sui, Zhe-Xue Chen, Wen-Na Du, Jian-Wei Shi, Qian Liu, Qing Zhang, Yong Zhang, Xin-Feng Liu
Summary: We have developed an efficient inch-scale SHG source through a solution-processed method by assembling gold nanoparticles with porous anodic alumina templates. Our device achieves multiresonance in both visible and near-infrared regions, providing strong electric field enhancement at the gap region. The SHG radiation produced is polarization-independent and shows wide-angle nonlinear response thanks to the unique geometry of the nanostructure.
Article
Materials Science, Multidisciplinary
Myeong-Su Ahn, Jaehun Jeon, Charles Soon Hong Hwang, Daniel S. Jeon, Min H. Kim, Ki-Hun Jeong
Summary: A compact hyperspectral camera using an active plasmonic tunable filter (APTF) with electrothermally driven spectral modulation is introduced. The APTF consists of angle-sensitive plasmonic structures (APS) over an electrothermal MEMS actuator. The compact camera provides feature-augmented images, making it suitable for biomedical applications.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Optics
Jingyan Zhan, Denghui Li, Domenico Bongiovanni, Yinxiao Xiang, Shengyao Chen, Yujie Zhang, Liqin Tang, Daohong Song, Jianke Yang, Roberto Morandotti, Zhigang Chen
Summary: We demonstrate that a weak nonlinear response of a probe beam can be modulated and controlled by a pump beam in plasmonic nanosuspensions, resulting in the generation of ring-shaped patterns. Gold nanosuspensions with strong nonlinear response is used as the medium for beam manipulation. The dynamics of hollow beam generation are examined in different nanosuspensions. This study enhances the understanding of nonlinear light-matter interactions and has potential applications in light control and optical limiting.
Article
Engineering, Electrical & Electronic
Yan Li, Muguang Wang, Pufeng Gao, Jing Zhang, Bin Yin, Chuncan Wang, Guofang Fan
Summary: In this letter, a novel photonics-assisted method for tunable microwave frequency comb (MFC) generation based on an actively mode-locked optoelectronic oscillator (AML-OEO) is proposed and experimentally demonstrated. The proposed method implements periodic gain modulation and widely tunable center frequency, using an externally introduced intensity-modulated optical signal and a microwave photonic filter (MPF) based on the phase-shifted fiber Bragg grating (PS-FBG). The AML-OEO operates in a stable multimode oscillation state and can generate MFC signals. Through adjusting the center frequency of the MPF, the center frequency of the generated MFC can be changed accordingly. In the proof-of-principle experiment, MFC signals with tunable center frequencies from 3.5 GHz to 6.5 GHz and frequency intervals of 1.02 MHz and 340.46 kHz are generated.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Optics
Jin Zhang, Depei Zhang, Maolong Zhang, Daikun Zheng, Anle Wang, Xiaotong Liu, Lei Hu, Xiaoniu Peng, Yalan Wang
Summary: A tunable microwave-pulse-generation scheme based on an actively mode-locked optoelectronic oscillator (OEO) using a microwave photonic filter (MPF) is proposed and demonstrated. The MPF consists of a phase-shifted fiber Bragg grating (PS-FBG) and a phase modulator. By injecting an external signal, microwave pulse trains with variable repetition rates can be generated, and the center frequency of the pulses can be tuned by adjusting the laser frequency. The proposed scheme has potential applications in pulse Doppler radar and communications.
Article
Materials Science, Multidisciplinary
Binghui Li, Yu-Sheng Lin
Summary: We introduce four types of tunable terahertz metamaterials made of split-ring resonators (SRRs) with different splits and inner movable structures. These designs can achieve different tuning ranges in transverse electric (TE) and transverse magnetic (TM) modes, exhibiting polarization-dependent and polarization-independent characteristics. By increasing the height of the inner movable structure, the resonant frequency of the metamaterials can be tuned. These designs possess anti-vibration and tunable characteristics, which make them potential candidates for high tunability, flexibility, and applicability in THz-wave optoelectronic devices.
MATERIALS RESEARCH BULLETIN
(2023)
Article
Chemistry, Multidisciplinary
Eva Prinz, Grisha Spektor, Michael Hartelt, Anna-Katharina Mahro, Martin Aeschlimann, Meir Orenstein
Summary: By tailoring the local and global geometries of vortex generators, arbitrary switching in the delivered plasmonic angular momentum can be achieved, providing a new method for plasmonic manipulation. The precise control over the generation and rotation direction of high-order plasmonic vortices was demonstrated, as well as the capability to create complex topological fields.
Article
Engineering, Electrical & Electronic
Haiming Li, Zhipeng Xu, Hongyang Wang, Jianping Chen
Summary: In this paper, a tunable multifrequency electromagnetically induced transparency-like (EIT-like) based on polarization modulation is theoretically and numerically demonstrated. The proposed metasurface consists of a single ring (SR) and H shape cut wire (HM) on the top layer, and a pair of split-ring resonators (SRRs) on the bottom layer, which can achieve tunable spectral responses in different polarization directions. Theoretical calculation based on the coupled Lorentz oscillator models agrees with the simulation results. Therefore, this metamaterial has great application prospects in slow light devices, nonlinear devices, optical data storage, quantum information technology and sensor fields, as it can achieve tunable EIT-like effect by adjusting the polarization direction.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Optics
Airong Zhao, Aline Pham, Aurelien Drezet
Summary: This multifunctional compact device integrates a polarization beam splitter and an orbital angular momentum generator, achieving vortex generation and splitting in transmission mode. Experimental demonstrations are conducted under a linearly polarized incident beam, utilizing polarization tomography as the analysis method. The technology is expected to have applications in chip-level beam shaping and high-capacity communication.
Article
Optics
Pengcheng Liu, Shangqing Shi, Mengjia Lu, Dongdong Lin, Wei Cheng, Tong Lin, Guohua Hu, Binfeng Yun, Yiping Cui
Summary: This article demonstrates a tunable microwave frequency comb (MFC) by injecting a low-frequency electrical signal into a tunable optoelectronic oscillator (OEO). The tuning of the comb's center frequency and spacing allows a frequency range of 1 to 22 GHz and obtains 50 comb lines in the MFC generator.
Article
Materials Science, Multidisciplinary
Zhongquan Nie, Xiaopeng Liu, Xiaofei Liu, Hengjing Wang, Dan Wang, Ensi Cao
Summary: This paper proposes and demonstrates the generation of ultrafast tunable super-oscillation light fields by tightly focusing a radially polarized Gaussian femtosecond laser. The light fields in the focal region can be converted from an Airy spot to a super-resolved spot as time goes on within one-half cycle. The study also uncovers the rapid evolutions of various properties of focused superoscillatory spots, supporting ultrafast adjustable super-oscillation light fields.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Qianlong Kang, Dekui Li, Kai Guo, Jun Gao, Zhongyi Guo
Summary: This paper proposes a tunable thermal emitter consisting of metal-insulator-metal (MIM) plasmonic metamaterial based on phase-change material Ge2Sb2Te5 (GST) to achieve tunable control of thermal radiation in wavelength ranges from 3 μm to 14 μm. The emitter possesses near unity emissivity at 6.3 μm wavelength for increased radiation heat dissipation, maintaining thermal stability. The emitter also offers thermal camouflage in the atmospheric window range of 3-5 μm for various background temperatures and environmental backgrounds.
Article
Physics, Multidisciplinary
Koijam Monika Devi, Arun Jana, Ajinkya Punjal, Nityananda Acharyya, Shriganesh S. Prabhu, Dibakar Roy Chowdhury
Summary: In this study, a dynamically tunable polarization independent slow light system is demonstrated via electromagnetically induced transparency (EIT) in a terahertz (THz) metasurface. The results show that the group delay and delay bandwidth product values of the slow THz light can be modulated by adjusting the pump fluence, resulting in a significant change in group velocity. This tunable slow light system has potential applications in delay lines and other ultrafast devices for the THz domain.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
Minsu Park, Jae-Young Yoo, Tianyu Yang, Yei Hwan Jung, Abraham Vazquez-Guardado, Shupeng Li, Jae-Hwan Kim, Jaeho Shin, Woo-Youl Maeng, Geumbee Lee, Seonggwang Yoo, Haiwen Luan, Jin-Tae Kim, Hee -Sup Shin, Matthew T. Flavin, Hong -Joon Yoon, Nenad Miljkovic, Yonggang Huang, William P. King, John A. Rogers
Summary: Thermal sensations play a crucial role in our perception of the physical world. Being able to recreate these sensations wirelessly through computer control can enhance virtual experiences in areas beyond video, audio, and haptic inputs. This article presents the development of a skin-integrated technology that generates thermal sensations across the skin with power efficiency and real-time control. The system utilizes passive cooling mechanisms, switchable thermal barrier interfaces, resistive heaters, and flexible electronics with wireless interfaces to portable devices, the internet, and cloud data infrastructure. Experimental studies and simulations guide the design choices, and demonstrations showcase applications in thermoregulation, social interactions, and sensory expansion.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Robotics
Yongdeok Kim, Yiyuan Yang, Xiaotian Zhang, Zhengwei Li, Abraham Vazquez-Guardado, Insu Park, Jiaojiao Wang, Andrew I. Efimov, Zhi Dou, Yue Wang, Junehu Park, Haiwen Luan, Xinchen Ni, Yun Seong Kim, Janice Baek, Joshua Jaehyung Park, Zhaoqian Xie, Hangbo Zhao, Mattia Gazzola, John A. Rogers, Rashid Bashir
Summary: Bioengineering approaches combined with three-dimensional scaffolds can be used to develop miniature robots. These robots, equipped with battery-free and microinorganic light-emitting diodes, can be wirelessly controlled and communicate in real-time. Through computational design and optimization, researchers have achieved remote control of walking, turning, plowing, and transport functions in these robots, paving the way for biohybrid machines that combine biological actuation and sensing with on-board computing.
Article
Engineering, Electrical & Electronic
Zhenyi Luo, Yuqiang Ding, Yi Rao, Shin-Tson Wu
Summary: The pancake lens structure offers a compact solution for near-eye displays, but the use of a half mirror results in a significant optical loss. The proposed folded optical structure, using polarization-selective cholesteric liquid crystal reflectors, doubles the efficiency and optical path length to balance the tradeoff between form factor and efficiency. Simulation results match well with experiments. Two display configurations are established to evaluate the imaging performances of the proposed pancake lens structure.
JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY
(2023)
Article
Engineering, Electrical & Electronic
En-Lin Hsiang, Zhiyong Yang, Shin-Tson Wu
Summary: Virtual reality (VR) devices use imaging optics to magnify microdisplay images, providing an immersive viewing experience. Microdisplays need high-resolution density and dynamic range to meet human vision system requirements. However, increasing resolution and dynamic range can reduce optical efficiency and complicate microdisplay panel fabrication. This paper analyzes image degradation in VR devices caused by both imaging optics and microdisplay, finding that imaging optics significantly impact microdisplay requirements, such as contrast ratio, local dimming zones, and resolution density. These findings help prevent excessive microdisplay design in pancake lens-based VR headsets.
JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY
(2023)
Article
Engineering, Electrical & Electronic
Yuqiang Ding, Yannanqi Li, Qian Yang, Shin-Tson Wu
Summary: This paper proposes a single full-color waveguide AR display based on reflective polarization volume gratings (PVGs) to improve stability and wearing comfort. By analyzing the optical system, we optimize a three-layer PVG as an in-coupler and derive the field of view limit. With a single-layer, thin PVG as an out-coupler, we achieve a relatively uniform exit pupil of 8 mm at the horizontal pupil expansion direction.
JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY
(2023)
Editorial Material
Optics
En-Lin Hsiang, Shin-Tson Wu
Summary: Compared to conventional bulky spectropolarimeters, computational spectropolarimeters reconstruct light-field information in a compact form factor, enabling new applications. A tunable liquid crystal metasurface can modulate the phase and spectral information of light, paving the way for developing compact and low-cost spectropolarimetric imaging devices with widespread applications.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Zhiyong Yang, Yizhou Qian, Junyu Zou, Chia-Lun Lee, Chih-Lung Lin, Shin-Tson Wu
Summary: To achieve high resolution and low power consumption in virtual reality applications, field sequential color (FSC) is used to triple the resolution density and optical efficiency of LCDs. By evaluating the physical properties of a high birefringence nematic LC mixture, a fringe-field switching (FFS) LCD was designed to exhibit fast response time for FSC operation. The FSC LCD also demonstrated wide color gamut and superior color uniformity.
APPLIED SCIENCES-BASEL
(2023)
Article
Multidisciplinary Sciences
Joseph W. Song, Hanjun Ryu, Wubin Bai, Zhaoqian Xie, Abraham Vazquez-Guardado, Khizar Nandoliya, Raudel Avila, Geumbee Lee, Zhen Song, Jihye Kim, Min-Kyu Lee, Yugang Liu, Mirae Kim, Huifeng Wang, Yixin Wu, Hong-Joon Yoon, Sung Soo Kwak, Jaeho Shin, Kyeongha Kwon, Wei Lu, Xuexian Chen, Yonggang Huang, Guillermo A. Ameer, John A. Rogers
Summary: Chronic wounds, especially those related to diabetes, pose a growing threat to public health and have significant economic impacts. Inflammation in these wounds disrupts the natural electrical signals that aid in healing, leading to slow migration of keratinocytes. This study presents a wireless, battery-free bioresorbable electrotherapy system that successfully overcomes practical engineering challenges and lack of monitoring capabilities. The system promotes accelerated wound closure by guiding epithelial migration, modulating inflammation, and promoting vasculogenesis, as demonstrated in a diabetic mouse wound model. Changes in impedance provide a means to track the healing process.
Article
Multidisciplinary Sciences
Pablo Cencillo-Abad, Daniel Franklin, Pamela Mastranzo-Ortega, Javier Sanchez-Mondragon, Debashis Chanda
Summary: All current commercial colors are pigment-based, which have limitations such as fading, instability in atmosphere, and environmental toxicity. The development of artificial structural coloration has been hindered by the lack of design ideas and impractical nanofabrication techniques. However, a self-assembled subwavelength plasmonic cavity has been presented as a solution to these challenges, allowing for angle and polarization-independent vivid structural colors. This platform, fabricated through large-scale techniques, offers a lightweight paint option with full coloration using just a single layer of pigment.
Article
Optics
Zhenyi Luo, Yannanqi Li, John Semmen, Yi Rao, Shin-Tson Wu
Summary: This study demonstrates an achromatic diffractive liquid-crystal device to overcome the chromatic aberration issue. The proposed device consists of three stacked diffractive liquid crystal optical elements with specific spectral response and polarization selectivity. Simulation and experimental results show significant improvement in imaging performance. This technology has potential applications in virtual reality and mixed reality fields.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Crystallography
Yizhou Qian, Zhiyong Yang, En-Lin Hsiang, Qian Yang, Kevin Nilsen, Yu-Hsin Huang, Kuan-Heng Lin, Shin-Tson Wu
Summary: Vehicle displays are becoming increasingly integrated into our daily lives, requiring high-resolution density and sufficient brightness to combat intense ambient light. Infotainment displays demand over 800 nit brightness to display images clearly under direct sunlight, while head-up displays need to strike a delicate balance between resolution density, brightness, transparency, and image quality.
Article
Optics
Chien-Chung Lin, Yuh-Renn Wu, Hao-Chung Kuo, Matthew S. Wong, Steven P. Denbaars, Shuji Nakamura, Ayush Pandey, Zetian Mi, Pengfei Tian, Kazuhiro Ohkawa, Daisuke Iida, Tao Wang, Yuefei Cai, Jie Bai, Zhiyong Yang, Yizhou Qian, Shin-Tson Wu, Jung Han, Chen Chen, Zhaojun Liu, Byung-Ryool Hyun, Jae-Hyun Kim, Bongkyun Jang, Hyeon-Don Kim, Hak-Joo Lee, Ying-Tsang Liu, Yu-Hung Lai, Yun-Li Li, Wanqing Meng, Haoliang Shen, Bin Liu, Xinran Wang, Kai-ling Liang, Cheng-Jhih Luo, Yen-Hsiang Fang
Summary: Micro light-emitting diode (micro-LED) is expected to play a significant role in future smart displays, offering advantages in various applications. The article focuses on the current status, challenges, and potential advances in micro-LED technology, highlighting the importance of epitaxy innovation and quantum scale structures. Peripheral components and technologies, such as microchip transfer and repair, heterogeneous integration, and novel 2D materials, are also discussed. The potential of micro-LED displays in augmented reality (AR) and the efforts to address existing problems are emphasized.
JOURNAL OF PHYSICS-PHOTONICS
(2023)
Article
Optics
Jianghao Xiong, Haizheng Zhong, Dewen Cheng, Shin-Tson Wu, Yongtian Wang
Summary: This study demonstrates a polarization hologram with full DoF for local manipulation of optical structure, based on emerging self-assembled photo-aligned liquid crystal technology. The ability to record arbitrary wavefront and perform local liquid crystal adjustment is achieved through freeform surface exposure and inkjet printing, respectively, resulting in a full-color retinal scanning display without color crosstalk.
Review
Optics
Yuqian Ding, Qian Yang, Yannanqi Li, Zhiyong Yang, Zhengyang Wang, Haowen Liang, Shin-Tson Wu
Summary: This review paper focuses on the perspectives and challenges of optical waveguide combiners for augmented reality (AR) displays. It introduces the basic device structures and operation principles of different AR architectures, and delves into different waveguide combiners, including geometric and diffractive waveguide combiners. Commonly used in-couplers and out-couplers are discussed, and their properties are analyzed in detail. The paper also explores recent advances in waveguide combiner design and modeling, and discusses the bottlenecks and future development trends in waveguide combiner technologies.
Article
Crystallography
Yuge Huang, Shin-Tson Wu
Summary: The Mini-LED backlit LCD exhibits premium display performance, including motion blur reduction, high dynamic range, and suppression of the halo effect.
LIQUID CRYSTALS TODAY
(2023)
