- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Photonic generation of high-purity 60?GHz millimeter-wave signal requiring only 10?GHz radio frequency local oscillator
摘要： A novel approach to generate 60 GHz millimeter-wave from a 10 GHz radio frequency signal using an integrated nested DD-MZM without optical filter is proposed and demonstrated. The simulation results show that the generated frequency sextupling optical mm-wave has high purity with an OSSR exceeding 29 dB and a RFSSR of 25 dB, which is consistent with the theoretical analysis. Besides, a RoF link model is established to investigate the transmission performance. The eye diagram keeps clear even when the optical mm-wave is transmitted over 60 km and the power penalty is about 0.4 dB after fiber transmission of 50 km.
关键词： Optical fiber communication,Dual-drive Mach–Zehnder modulator (DD-MZM),Optical millimeter-wave generation
更新于2025-09-23 15:23:52
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Filterless frequency octupling circuit using dual stage cascaded polarization modulators
摘要： This paper demonstrates the photonic generation of millimetre-wave carriers by frequency octupling of a radio frequency (RF) carrier using a circuit with two parallel arms each containing two polarization modulators in series. The low RF drive power required and the absence of optical filters make this architecture suitable for generating highly stable and tunable optical millimetre-waves. A transfer function representation is used to analyse the operation and a simulation using Virtual Photonic Inc. software package is presented as a proof of concept. The simulation results show very high unwanted optical and electrical side harmonic suppression ratio for a wide range of modulation index compared to the prior art. Further, considering the practical scenario, operating tolerance against the imbalances in the key parameters is established. The unwanted RF sidebands are more than 19 dB and 30 dB below the desired signal power even when a deviation of ±3° is considered in individual RF phase and polarizer angle respectively.
关键词： Optical millimetre wave generation,polarization modulator,frequency octupling,polarizer
更新于2025-09-23 15:19:57
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Time-resolved measurements of two-color laser light emitted from GaAs/AlGaAs-coupled multilayer cavity
摘要： We measured the two-color laser oscillation from a GaAs/AlGaAs-coupled multilayer cavity at 18 °C–42 °C using current injection. We confirmed simultaneous lasing by detecting the sum frequency generation signal generated by the two-color laser light, and performed time-resolved measurement using a streak camera with a spectrometer. From the observed time transient of the spectra at various temperatures, it is clarified that the temperature change of the device, induced by current injection, modulates the effective cavity length. Therefore, the temperature control of the device is a key factor in stable two-color lasing and THz wave generation.
关键词： time-resolved measurements,sum frequency generation,THz wave generation,GaAs/AlGaAs-coupled multilayer cavity,two-color laser
更新于2025-09-19 17:13:59
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[IEEE 2018 International Symposium on Micro-NanoMechatronics and Human Science (MHS) - Nagoya, Japan (2018.12.9-2018.12.12)] 2018 International Symposium on Micro-NanoMechatronics and Human Science (MHS) - Uniform Transfection: Shock Wave Generation in Laser Ablation and Microcontact Printing
摘要： With the increasing need of regenerative medicines, cell therapy, and biopharmaceutical drug, it is necessary to develop a method for massively parallel delivery and uniform transfection. This research explores the possibility of using μCP (using cell adhesive and cell blocking agents) for printing massive number of cells on a substrate and using optoporation methods (nano-second pulsed radiation) to perforate cell membranes. With combining these two methods, a stand-alone micro-device capable of performing localized intracellular delivery will be developed. In this paper, we confirmed the generation of shock wave upon optoporation, tried intra-cellular delivery using Calcein, develop the stamp for micro-contact printing and performed the printing.
关键词： optoporation,laser ablation,uniform transfection,shock wave generation,microcontact printing
更新于2025-09-19 17:13:59
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Complete Scene Reconstruction by Merging Images and Laser Scans
摘要： Optical fibre transmission has enabled greatly increased transmission rates with 10 Gb/s common in local area networks. End users find wireless access highly convenient for mobile communication. However, limited spectrum availability at microwave frequencies results in per-user transmission rates limited to much lower values, e.g., 500 Mb/s for 5-GHz band IEEE 802.11ac. Extending the high data-rate capacity of optical fiber transmission to wireless devices requires greatly increased carrier frequencies. This paper will describe how photonic techniques can enable ultrahigh capacity wireless data distribution and transmission using signals at millimeter-wave and TeraHertz (THz) frequencies.
关键词： photonic integrated circuits,microwave photonics,Broadband communication,optical mixing,optical heterodyne,millimeter (mm)-wave generation,optical phase lock loops,semiconductor lasers
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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[IEEE 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Aswan City, Egypt (2019.10.23-2019.10.25)] 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Analysis, Design and Simulation of a DC Photovoltaic Microgrid with Electric Vehicle Charging Capability
摘要： Optical fibre transmission has enabled greatly increased transmission rates with 10 Gb/s common in local area networks. End users find wireless access highly convenient for mobile communication. However, limited spectrum availability at microwave frequencies results in per-user transmission rates limited to much lower values, e.g., 500 Mb/s for 5-GHz band IEEE 802.11ac. Extending the high data-rate capacity of optical fiber transmission to wireless devices requires greatly increased carrier frequencies. This paper will describe how photonic techniques can enable ultrahigh capacity wireless data distribution and transmission using signals at millimeter-wave and TeraHertz (THz) frequencies.
关键词： optical heterodyne,optical mixing,optical phase lock loops,millimeter (mm)-wave generation,microwave photonics,photonic integrated circuits,Broadband communication,semiconductor lasers
更新于2025-09-19 17:13:59
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[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Frequency-and-polarization-controllable High-power THz Wave Generation Using Organic Nonlinear Optical Crystal
摘要： Arbitrary control of high-power THz polarization and frequency is studied by the numerical calculation based on the coupled wave approach. THz wave generation using organic crystals via optical rectification provides high conversion efficiency. To overcome the limitation of the generated THz field direction which comes from their optical anisotropy, we propose the synthesis of THz wave generated from two crystals whose optical axis are orthogonal each other. By the calculation, the linearly and circularly polarized THz wave generation by changing the time delay of two pump pulses is demonstrated.
关键词： optical rectification,organic nonlinear optical crystal,polarization control,frequency control,THz wave generation
更新于2025-09-16 10:30:52
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[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Terahertz Wave Generation Using Single or Few-cycle Laser Pulses in a Gaseous Medium
摘要： We perform theoretical calculations to demonstrate that single or few-cycle laser pulses (at the wavelength of 800 nm) can generate an intense terahertz emission by a directional current. Terahertz (THz) radiation exhibits a strong dependence on the carrier-envelope phase (CEP) of the driving laser pulse as the duration decreases. The strength of the THz radiation is pronounced at the CEP of 90 deg. The design of an experimental setup to demonstrate THz wave generation using single or few-cycle laser pulses in a gaseous medium is also demonstrated.
关键词： directional current,single or few-cycle laser pulses,Terahertz wave generation,carrier-envelope phase (CEP)
更新于2025-09-16 10:30:52
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Anisotropic Dispersive Shock Waves in Highly Nonlinear M-Cresol/Nylon
摘要： M-Cresol/Nylon is a chemical solution, which is made up of an organic solvent (m-cresol) and a synthetic polymeric solute (nylon). Recent experiments showed that this solution exhibits an isotropic giant self-defocusing nonlinearity, tunable by varying the nylon concentration [1]. When it is enlightened by a continuous-wave laser beam, light absorption induces heat gain, which reduces the refractive index: the material experiences a nonlinear thermo-optical effect, made nonlocal by the heat diffusion. Since the temperature changes with the beam intensity, this nonlinearity follows a nonlocal Kerr model, expressed by the nonlinear Schroedinger equation (NLSE) [2]. In particular, V. Smith et al. measured the m-cresol/nylon nonlinear Kerr coef?cient n2 and found that, if for pure m-cresol it is ?9 × 10?8cm2/W , for a nylon mass concentration of 3.5% it is ?1.6 × 10?5cm2/W , a magnitude higher than most of the other thermal nonlinear materials reported in literature. In optics, many phenomena are ruled by NLSE, such as soliton propagation and dispersive shock wave (DSW) generation [1,2]. We report experimental evidence of two-dimensional optical DSWs with an anisotropic zero-singularity (Fig. 1). Fixing z as the longitudinal and x, y as the transverse directions, we start with a beam that has a Gaussian pro?le along y but a Gaussian ?rst derivative along x, thus the intensity is null for x = 0. This speci?c initial condition causes a new phenomenon, reported here for the ?rst time: the shock develops undular bores on the beam external borders (as already known in literature [2]), but around the singularity it presents an abrupt intensity discontinuity. We theoretically analyze the wave breaking along all the propagation. By a hydrodynamic model, we study the beam before the shock point: the WKB approach and the characteristic method let us predict the wave breaking both in phase and in intensity [2]. In order to model the beam propagation beyond the shock point, we use mathematical tools of time asymmetric quantum mechanics and uncover the mechanism how such an abrupt intensity discontinuity is generated [3]. We numerically simulate these results and ?nd remarkable agreement both with experiments and with theoretical predictions. Our outcome not only con?rms previous studies on the giant nonlinear response of m-cresol/nylon, but also discloses fundamental insights on propagation of DSWs with a singular initial intensity pro?le.
关键词： Dispersive shock wave generation,Anisotropic Dispersive Shock Waves,Highly Nonlinear M-Cresol/Nylon,Nonlinear Schroedinger equation,Thermo-optical effect
更新于2025-09-16 10:30:52