A5102710591- Photonic and Optical Devices
- Advanced Photonic Communication Systems
- Organic Light-Emitting Diodes Research
- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Advanced Sensor and Energy Harvesting Materials
- Perovskite Materials and Applications
- Advanced Fiber Laser Technologies
- Semiconductor Quantum Structures and Devices
- Advanced Semiconductor Detectors and Materials
- Semiconductor Lasers and Optical Devices
- Green IT and Sustainability
- Luminescence and Fluorescent Materials
- Optical Network Technologies
- Advanced Optical Sensing Technologies
- 3D Printing in Biomedical Research
- Advanced Sensor and Control Systems
- Polyoxometalates: Synthesis and Applications
- GaN-based semiconductor devices and materials
- Advanced Antenna and Metasurface Technologies
- Transition Metal Oxide Nanomaterials
- Electromagnetic Launch and Propulsion Technology
- Metamaterials and Metasurfaces Applications
- Modular Robots and Swarm Intelligence
- Polymer Surface Interaction Studies
University of Virginia
2023-2024
Peking University
2019-2023
Peking University Shenzhen Hospital
2022
Hong Kong University of Science and Technology
2021
University of Hong Kong
2021
Purdue University West Lafayette
2001-2002
Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in field photonics, whereby low-noise signals generated by down-conversion ultrastable optical references using a frequency comb
Abstract The fast development of mid-wave infrared photonics has increased the demand for high-performance photodetectors that operate in this spectral range. However, signal-to-noise ratio, regarded as a primary figure merit detection, is strongly limited by high dark current narrow-bandgap materials. Therefore, conventional such HgCdTe require cryogenic temperatures to avoid excessively current. To address challenge, we report an avalanche photodiode design using photon-trapping structures...
Abstract In this work, the multilayer organic light emitting transistors (OLETs) based on high‐ k polymer crosslinked poly(vinyl alcohol) (C‐PVA) as dielectric layer are studied. The devices show an excellent brightness of 14 500 cd m −2 and a record breaking external quantum efficiency (EQE) about 9.0% in inert atmosphere. use perfluoro(1‐butenyl vinyl ether) (CYTOP) modified C‐PVA hydrophobic affords OLETs with good stability, displaying maximum 13 400 EQE 7.31% ambient conditions high...
Current power supply networks across the world are mostly based on three-phase electrical systems as an efficient and economical way for generation, transmission distribution of electricity. Now, many electrically driven devices relying direct current or single-phase alternating that complicates utilization by requiring additional elements costly switching mechanisms in circuits. For example, light-emitting devices, which now widely used displays, solid-state lighting etc. typically operate...
High-sensitivity avalanche photodiodes (APDs) are used to amplify weak optical signals in a wide range of applications, including telecommunications, data centers, spectroscopy, imaging, light detection and ranging, medical diagnostics, quantum applications. This paper reports antimony-based separate absorption, charge, multiplication structure APDs on InP substrates. Al0.7In0.3As0.79Sb0.21 is for the multiplier region, InGaAs as absorber. The excess noise comparable that silicon APDs;...
Abstract Solution‐processable electrochromic polymers (ECPs) with high performance are urgently needed for extensive applications. Nevertheless, they suffer from slow switching speed because of low ionic conductivities. Herein, we present an effective strategy to improve the contrast and in ECPs via facile side‐chain engineering. A novel thieno[3,2‐ b ]thiophene‐based polymer (PmOTTBTD) is designed successfully synthesized by introducing oligo(ethylene oxide) side chains conductivity....
Organic light-emitting diodes (OLEDs) manifest a high performance that has enabled the industrial applications of this technology; nevertheless, achieving efficiency in these devices via introducing dopants makes fabrication process quite complicated. In Letter, we demonstrate color-tunable organic (CT-OLEDs) with simplified structure incorporates dopant-free PN heterojunction as emitting layer. By depositing hole transport layer, 1,1-bis[(di-4-tolylamino)phenyl] cyclohexane (TAPC) P-region...
Abstract Exploring multifunctional, miniaturized light‐emitting devices with well‐controlled operation is deemed vital to meet the increasing demands of full‐color displays and lighting systems. Nevertheless, complicated architectures, low performance, poor operational control remain daunting challenges in realization smart devices. Here, an alternating‐current‐driven organic triode (AC‐OLETr) reported simple yet versatile architecture that emits light precise over color intensity. The...
Micropatterning of polypyrrole films can be achieved via vacuum deposition monomers, followed by UV-induced selective polymerization (see Figure). This fabrication process minimizes the surface roughness separation monomer and subsequent polymerization. Vacuum has additional advantage forming that have low contamination levels possess a well-defined thickness morphology.
Transparent amorphous germanium (a‐Ge) has emerged as a promising material for engineering nanostructures and metasurfaces, offering significant potential enhancing the performance of photonic devices in short‐wavelength infrared (SWIR) spectrum. Herein, successful application a‐Ge metasurfaces with truncated pyramid profile to enhance external quantum efficiency (EQE) digital alloy Al 0.3 InAsSb p–i–n photodiode across broad‐wavelength range SWIR is presented. The experimental findings...
Abstract Limited to the structure of traditional light‐emitting devices, electronic devices that can directly convert machine language into human visual information without introducing any back‐end circuit are still not easy achieve. Based on a specially designed three‐phase co‐planar electrode structure, new type alternating current driven organic device with integration emission and control functions, full‐color tunability simple is demonstrated in this study. We integrate function...
Thin polystyrene films were formed on polycrystalline platinum by styrene deposition followed UV-initiated polymerization under cryogenic, ultrahigh-vacuum conditions. Temperature-programmed desorption (TPD) experiments showed that chemisorbs weakly the Pt surface. In temperature region of 115−145 K, adsorbed undergo a crystallization process can be described Avrami equation. The rate increased with incident UV intensity, as expected, but was found to decrease increasing temperature, most...
The thermal properties of modified uni-traveling carrier (MUTC) photodiode flip-chip bonded to AlN and diamond are simulated. impedance InGaAs is the primary source internal heating. An n-down epitaxial structure designed improve dissipation. Compared conventional p-down configuration, MUTCs diamond, or submounts achieved 145% 110% improvement in dissipated power density at failure, respectively. improved characteristics presage higher RF output before failure.
We have demonstrated InGaAs/AlInAsSb separate absorption, charge, and multiplication avalanche photodiodes. The gain, excess noise, temperature-dependent dark current been characterized. APDs were grown on semi-insulating InP substrates, which is beneficial for bandwidth improvement compared to AlInAsSb GaSb substrates.
Modern communication, navigation, and radar systems rely on low noise frequency-agile microwave sources. In this application space, photonic provide an attractive alternative to conventional synthesis by leveraging high spectral purity lasers optical frequency combs generate microwaves with exceedingly phase noise. However, these techniques suffer from a lack of tunability, also have substantial size, weight, power requirements that largely limit their use laboratory settings. work, we...
Using integrated photonic chip components for ’2-point’ optical frequency division, we generate a 20 GHz microwave signal with phase noise of –135 dBc/Hz at 10 kHz offset.
A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-20976-0.
An n-down MUTC epitaxial structure is designed to improve thermal dissipation. The performance of devices has been simulated. flip-chip bonded heat sinks are demonstrated characteristics and presage higher RF output power before failure.