- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Plasmonic Micro-Antenna Characteristics Using Gold Grating Embedded in a Panda-Ring Circuit
摘要： An investigation of the plasmonic micro-antenna characteristics using an optical modified add–drop multiplexer embedded gold grating is proposed. A device consisting of a main microring and two nano-ring phase modulators is known as a Panda-ring resonator. A gold grating is embedded at the main ring center to induce plasmonic polariton, which is the plasmonic wave that oscillates with plasma frequency. At the resonance, the whispering gallery mode (WGM) of propagation light fields can be obtained by controlling the two suitable side ring parameters, from which the plasma resonant frequency is obtained by the graphical method called the Optiwave program. In manipulation, the light source with the wavelength of 1.55 μm is fed into the system. The input power was varied from 1 to 10 mW, from which the Bragg wavelength at the resonant peak is employed for all calculations. The directivity and gain of the plasmonic micro-antenna of 2.8 mW (4.47 dBm) and 0.78 mW (? 1.08 dBm) are obtained. The motivation for this study is that the plasmonic micro-antenna enhances the performance of optical/communication devices due to its extraordinary properties. The key finding is the operation of the plasmonic micro-antenna at optical frequencies using the Panda-ring circuit, which has dual modes for wireless and cable connections. In applications, the large-area antenna (multi-antennas) has the potential for atom, cell, and brain communication network investigations; regarding the linear relation- ship trend of the output gain, the use of the circuit for application in sensors is also possible.
关键词： Gold grating,Plasmonic antenna,THz frequency,Add–drop multiplexer,Panda ring
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 2nd International Conference on Information Communication and Signal Processing (ICICSP) - Weihai, China (2019.9.28-2019.9.30)] 2019 IEEE 2nd International Conference on Information Communication and Signal Processing (ICICSP) - Vision-based Automatic Detection of Suspended Solids in Bottled Mineral Water
摘要： Terahertz (THz) cameras comprising an uncooled micro-bolometer array have been developed for simple THz imaging, and the improvement of their sensitivity is one of the important issues. We fabricated a new micro-bolometer array with a resonant cavity structure for a real-time THz camera, alongside a new method for evaluating the sensitivity across a wide range of the THz frequency region. The frequency dependence of the sensitivity of the THz camera is measured in the 0.5–2.0-THz frequency range taking the polarization dependence into account. It was found that the resonant cavity structure effectively increased the sensitivity of the THz camera, and, actually, the improvement by one order of magnitude was achieved in the frequency range below 1 THz. The THz camera with much enhanced sensitivity will expand the frontiers of real-time THz imaging such as molecular imaging and nondestructive inspection.
关键词： focal plane array,micro-bolometer,terahertz (THz),real-time imaging,Compact terahertz camera
更新于2025-09-19 17:13:59
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[IEEE 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA) - Xi'an, China (2019.6.19-2019.6.21)] 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA) - Research and Application of Remote Removal of Floating Foreign Objects on Transmission Lines Based on Fiber Laser
摘要： We present a detailed investigation of the responsivity and the noise in room temperature THz direct detectors made of YBa Cu O (YBCO) thin-film nano-bolometers. The YBCO nano-bolometers are integrated with planar spiral antennas covering a frequency range from 100 GHz to 2 THz. The detectors were characterized at 1.6 THz, 0.7 THz, 400 GHz and 100 GHz. The maximum electrical responsivity of 70 V/W and a minimum noise equivalent power (NEP) of 50 pW/Hz were measured, whereas the highest optical responsivity was 45 V/W. The noise in nano-bolometers is independent on the device volume and for a given modulation frequency and a dc voltage Hz.
关键词： room temperature operation,YBa Cu O (YBCO) film,responsivity,THz detectors,Bolometer
更新于2025-09-19 17:13:59
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Xa??Shaped Alignment of Chromophores: Potential Alternative for Efficient Organic Terahertz Generators
摘要： Efficient broadband organic terahertz (THz) generators using X-shaped alignment of the nonlinear optical chromophores, as an alternative to the parallel alignment of chromophores in benchmark organic crystals, are reported. All the developed six organic benzothiazolium crystals exhibit an isomorphic X-shaped alignment of chromophores, resulting in an unprecedentedly large off-diagonal optical nonlinearity (>100 × 10?30 esu), which presents one of the largest off-diagonal optical nonlinearity of organic crystals. The benzothiazolium crystals exhibit efficient broadband THz wave generation employing the off-diagonal optical nonlinearity, in contrast to the present state-of-the-art organic THz generators that mostly utilize diagonal optical nonlinearity. For using off-diagonal and diagonal optical nonlinearities, the polarization of the optical pump is perpendicular and parallel, respectively, to the polar axis of crystals. In addition to a large THz wave generation efficiency with one order of magnitude higher peak-to-peak THz electric field than that generated in a 1.0-mm-thick inorganic benchmark ZnTe crystal, the benzothiazolium crystals generate broadband THz spectra with an upper cut-off frequency of near 8 THz, and the absence of strong absorption dimples in the range of 0.5?4 THz. Therefore, the X-shaped alignment of chromophores presents an interesting potential alternative for efficient broadband organic THz generators.
关键词： nonlinear optical crystals,THz generators,organic crystals
更新于2025-09-19 17:13:59
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Graphene based plasma-wave devices for terahertz applications
摘要： Unique properties of graphene are combined to enable graphene plasmonic devices that could revolutionize the terahertz (THz) electronic technology. A high value of the carrier mobility allows us to excite resonant plasma waves. The graphene bipolar nature allows for different mechanisms of plasma wave excitation. Graphene bilayer and multilayer structures make possible improved THz device configurations. The ability of graphene to form a high quality heterostructure with h-BN, black phosphorus, and other materials systems supports advanced heterostructure devices comprised of the best properties of graphene and other emerging materials. In particular, using black phosphorus compounds for cooling electron–hole plasma in graphene could dramatically improve the conditions for THz lasing. High optical phonon energy allows for reaching higher plasma frequencies that are supported by high sheet carrier densities in graphene. Recent improvements in graphene technology combined with a better understanding of the device physics of graphene THz plasmonics and graphene plasmonic device designs hold promise to make graphene THz plasmonic technology one of the key graphene applications. Commercialization of plasmonic graphene technology is facing the same challenges as other graphene applications, which have difficulties in producing uniform large graphene layers, bilayers, and heterostructures of high quality and making good low resistance stable Ohmic contacts. The time projection for large scale graphene electronic device applications now extends into the 2030s. However, emerging graphene mass production technologies might bring commercial applications of the graphene plasmonic terahertz technology closer.
关键词： heterostructures,graphene,black phosphorus,Ohmic contacts,plasma waves,THz technology,terahertz,plasmonic devices,optical phonon energy,carrier mobility
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - A phase field formulation of the coupled effects of defect generation and large strains on microstructure evolution during laser-based additive manufacturing
摘要： This paper presents a high-power 240–290 GHz waveguide enclosed two-dimensional (2-D) grid heterostructure barrier varactor (HBV) frequency multiplier. A 35 mW of output power is produced at 247 GHz with an input power of 900 mW. The operational bandwidth is tunable within a 50 GHz span by the use of an input tuner able to adjust the input matching of the 2-D grid HBV frequency multiplier. Tuning is achieved by moving a suspended dielectric slab in the input waveguide.
关键词： 2-D grid,quasi-optical,Frequency multipliers,impedance matching,tuners,THz sources,varactors,heterostructure barrier varactors (HBVs)
更新于2025-09-19 17:13:59
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Electromagnetic Characterization and Design Note of a Sub-THz SiGe Voltage-controlled Oscillator
摘要： In this paper we present the electromagnetic (EM) characterization and some design notes of a sub-Terahertz voltage-controlled oscillator (VCO) based on a push-push architecture and realized based on Colpitts-type oscillators. The circuit operates at both 0.192 GHz and 0.384 THz the frequencies and is implemented in a 130 nm SiGe bipolar technology provided by IHP foundry.
关键词： SiGe bipolar technology,push-push architecture,voltage-controlled oscillator,sub-THz,Colpitts-type oscillators
更新于2025-09-19 17:13:59
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Methyl Made Noncentrosymmetric Stacking: A Promising Organic Single Crystal for Highly Efficient Terahertz-wave Generation
摘要： Regulating secondary bonds in organic compounds is one of the important routes to design practical materials with excellent performances. However, it is still a great challenge to control molecular arrangement and spatial configuration by changing limited substituent groups. Herein, two indolium-based (C19H20NO)+ crystals, centric OHI-CBS and acentric OHI-T were synthesized and grown by evaporation method. An intriguing structural change from centrosymmetric (P21/c) to noncentrosymmetric (Cc) space group was obtained by a simple substitution from chloro- to methyl. Theoretical calculations demonstrate hydrogen bonds and π-π interactions make a dominated contribution to molecular spatial alignment. Meanwhile, OHI-T crystal exhibits prominent nonlinearity about 0.7 times that of the benchmark OH1 crystal, wide band gap (2.47 eV), wide transparency range (504 - 2100 nm), and remarkably efficient output energy among 0.1 - 20 THz region, suggesting it is a potential nonlinear optical media for THz-wave generation. This work realizes the rational crystal structural regulation by simple molecular subsitution and provides a feasible design strategy for other organic optoelectronic functional materials.
关键词： indolium-based crystals,π-π interactions,hydrogen bonds,THz-wave generation,nonlinear optical media
更新于2025-09-19 17:13:59
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High-Performance GaAs/AlAs Terahertz Quantum-Cascade Lasers For Spectroscopic Applications
摘要： We have developed terahertz (THz) quantum-cascade lasers (QCLs) based on GaAs/AlAs heterostructures for application-defined emission frequencies between 3.4 and 5.0 THz. Due to their narrow line width and rather large intrinsic tuning range, these THz QCLs can be used as local oscillators in airborne or satellite-based astronomical instruments or as radiation sources for high-resolution absorption spectroscopy, which is expected to allow for a quantitative determination of the density of atoms and ions in plasma processes. The GaAs/AlAs THz QCLs can be operated in mechanical cryocoolers and even in miniature cryocoolers due to the comparatively high wall-plug efficiency of around 0.2% and typical current densities below 500 A/cm2. These lasers emit output powers of more than 1 mW at operating temperatures up to about 70 K, which is sufficient for most of the abovementioned applications.
关键词： terahertz (THz) spectroscopy,Quantum-cascade laser (QCLs)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 6th International Symposium on Electromagnetic Compatibility (ISEMC) - Nanjing, China (2019.11.1-2019.11.4)] 2019 IEEE 6th International Symposium on Electromagnetic Compatibility (ISEMC) - Spoof Plasmon Resonance with Terahertz 1-D Periodic Rectangular Filled Refractive Index Sensor
摘要： the dispersion properties of spoof surface plasmon polaritons with 1D rectangular groove structure by analytical solution and numerical solution respectively is analyzed, and the FEM method was used to simulate the refractive index sensing of SPR in terahertz band in an Otto configuration. From the simulation results, we can see that the 1D periodic groove has strong field constraint ability in THz regime as well as in optical band, and the variation of reflection coefficient with incident angle and frequency is very sensitive to the refractive index of the analyte. These results provide a new approach to sample detection and THz regime refractive index sensing, which has great advantages in biomedical tissue detection and sample detection in the future.
关键词： FEM,Spoof Spps,dispersion,THz sensing,groove
更新于2025-09-19 17:13:59