- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Evidence of enhanced Zn-diffusion observed during the growth of Inverted Metamorphic Solar Cells
摘要： We present novel waveguide packaging for sub-millimeter and terahertz-wave devices, which is suitable for large chip-width MMICs and doesn’t require any additional fabrication process. With full electromagnetic simulation, we analyze possible wave modes in a rectangular waveguide with thin E-plane slits formed for inserting large-width MMICs into the split waveguide block and show that parasitic modes can be well suppressed by lossy and high-dielectric material. For a 1.1-mm-wide test IC in the 260–320 GHz band, measured transition loss is around 1 dB with more than 60 dB inter-port isolation.
关键词： terahertz wave,waveguide package,Integrated E-plane probe
更新于2025-09-19 17:13:59
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Tunable Terahertz Metamaterials Based on Anapole Excitation with Graphene for Reconfigurable Sensors
摘要： Anapole mode is excited by the destructive interference between the toroidal and electric dipoles moments, resulting in a high quality (Q)-factor. In this paper, we designed a high Q-factor metamaterial which shows anapole behaviors in terahertz region. Through introducing graphene, the destructive interference condition is disturbed and tunability can be realized. This pattern reflects brilliant tunability performance that frequency movements above 250 GHz per 0.1eV can be verified. Ingenious adjustment by the position of graphene offers the possibility of diversified tuning capabilities. Such a tunable terahertz metamaterial has great potential in reconfigurable sensors.
关键词： tunable,terahertz,metamaterial,graphene,anapole
更新于2025-09-19 17:13:59
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High power edge-cum-surface emitting terahertz laser arrays phased locked by vacuum guided plasmon waves
摘要： Terahertz semiconductor quantum-cascade lasers (QCLs) are widely implemented with metallic cavities that support low-loss plasmonic optical modes at long wavelengths. However, resonant optical modes in such cavities suffer from poor radiative characteristics due to their subwavelength transverse dimensions. Consequently, single-mode terahertz QCLs with metallic cavities and large (>100 mW) output power have only been realized in the surface-emitting con?guration that affords a large radiating surface. Here, we demonstrate a method to enhance radiative outcoupling from such plasmonic lasers for high-power emission in the edge-emitting (end-?re or longitudinal) direction. Single-sided plasmon waves propagating in vacuum are resonantly excited in surrounding medium of metallic cavities with the QCL semiconductor medium. The vacuum guided plasmon waves with a large wavefront phase-lock multiple metallic cavities longitudinally, which leads to intense radiation in multiple directions, including that in the longitudinal direction in a narrow single-lobed beam. The multicavity array radiates predominantly in a single spectral mode. A peak-power output of 260 mW and a slope ef?ciency of 303 mW/A are measured for the end-?re beam from a 3:3 THz QCL operating at 54 K in a Stirling cooler. Single-mode operation and lithographic tuning across a bandwidth of (cid:2)150 GHz are demonstrated.
关键词： quantum-cascade lasers,surface-emitting,plasmonic,phase-locking,edge-emitting,terahertz
更新于2025-09-19 17:13:59
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Graphene assisted terahertz metamaterials for sensitive bio-sensing
摘要： We report that single-stranded deoxyribonucleic acids (ssDNAs) at very low concentrations can be detected using graphene-combined nano-slot-based terahertz (THz) resonance. A combination of the resonant structure and tuned electro-optical properties of graphene can provide unprecedentedly sensitive biomolecule sensing even using very low energy THz photons, overcoming the huge scale di?erence of 10,000:1 between the wavelength and the size of the ssDNAs. Ultrahigh sensitivity is obtained by the signi?cant increase in the absorption cross-section of the graphene sheet with the targeted biomolecules, induced by strong THz ?eld enhancement at the resonance frequency inside the slots. Clearly distinguishable THz optical signals were observed between di?erent species of ssDNAs even at the nano-mole level and analyzed quantitatively in terms of the electro-optical properties of the suspended graphene layer modi?ed by the attached ssDNAs without any molecular-speci?c labeling for the THz regime. Quantitative analysis of ssDNA molecule adsorption was carried based on the change in conductivity using a theoretical THz transmission model.
关键词： Terahertz,Graphene,Metamaterial,Biosensor
更新于2025-09-19 17:13:59
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Frequency-tunable logic gates in graphene nano-waveguides
摘要： In this study, simple basic plasmonic logic gates of XOR, OR, and NOT based on graphene nano-ribbon resonators coupled to properly designed arrangements of nano-waveguides, as input and output logic ports, are demonstrated. The operation of the structures as frequency selective components is based on the propagation of edge modes in nano-waveguides and coupling to nano-ribbon resonators located in appropriate locations. The gates performance is investigated through analytic approaches and verified numerically using the finite difference time domain method. Typical extinction ratio of about 8 dB between ON and OFF logic states has been attained. According to the fantastic feature of voltage-dependent chemical potential of graphene conductivity, the characteristics of the structures can be actively manipulated. These sub-wavelength plasmonic components can be employed extensively in terahertz demanded applications.
关键词： Nano-ribbon resonator,Nano-waveguide,Logic gate,Plasmonic component,Graphene-based component,Terahertz spectra
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) - High Sensitivity Heterodyne Electro-Optic Sampling with 1.5-μm Laser Source
摘要： A detection module for the heterodyne electro-optic sampling of terahertz pulses composed of a GaAs plate inserted into a tapered parallel plate waveguide has been designed and fabricated. The detector was installed into a standard terahertz time-domain spectrometer with a 1.5-μm femtosecond laser as a light source. The spectral bandwidth of 3.5 THz and dynamic range of 5 orders of magnitude were experimentally demonstrated, even with a photo-conductive antenna designed for 800-nm as an emitter.
关键词： 1.5-μm femtosecond laser,GaAs plate,tapered parallel plate waveguide,heterodyne electro-optic sampling,terahertz pulses,terahertz time-domain spectrometer
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) - Generation of MV/cm longitudinal terahertz electric fields from relativistic laser-solid interactions
摘要： We report on the generation and detection of longitudinal terahertz (THz) transient, with field strength of 1.5 MV/cm [1], at the focus of a radially polarized high-power terahertz beam generated at the rear surface of a thin metal foil irradiated by multi-terawatt laser pulse [2]. An f/1.5 off-axis parabolic mirror was used to focus the collimated THz beam. In addition to the longitudinal field, a transverse field, albeit off-axis, with amplitude in excess of 3 MV/cm was also measured.
关键词： multi-terawatt laser pulse,field strength,high-power terahertz beam,off-axis parabolic mirror,longitudinal terahertz
更新于2025-09-16 10:30:52
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Sensitive Terahertz Free Space Modulator Using CsPbBr3 Perovskite Quantum Dotsa??Embedded Metamaterial
摘要： We have demonstrated a method for active modulating terahertz wave using CsPbBr3 perovskite quantum dots (QDs)–embedded double-C metallic metamaterial unit cells. The resonance response frequency of the proposed CsPbBr3 perovskite QDs-embedded metamaterial can be tuned by varying the external applied photoexcitation intensity. By doing so, we measured the dynamic terahertz wave transmission modulation and demonstrate tuning of the terahertz wave resonant response based on the optical pump fluences. The modulation speed and depth of the modulator are 5 MHz and 88.3%, respectively. Our results indicate the importance of manipulating the terahertz wave for future wireless communication.
关键词： Terahertz modulation,CsPbBr3 perovskites quantum dots,Terahertz wave
更新于2025-09-16 10:30:52
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Tunable Triple-Band Plasmonically Induced Transparency Effects Based on Double π-Shaped Metamaterial Resonators
摘要： Tunable triple-peaks with the transmission intensity of more than 90% plasmonically induced transparency metamaterial resonator based on nested double π-shaped metallic structure is proposed at the terahertz frequency region, which is consisted of three sets of gold nanorods with different sizes placed on a dielectric substrate of SiO2. The coupling effect of localized electric field between different parts of the proposed structure can be used to explain the physical mechanism of three transparent windows. The finite-difference time-domain (FDTD) is used to study the spectral properties of the proposed structure, and the influence of the size of the nanorods and the relative distance between them on the spectral characteristics are also discussed. It can be seen that some obvious shift phenomena occur in the spectra with the change of these nanorods. These results indicate that the proposed structure opens up new avenues in many related applications, especially for multi-channel filters, optical switches, and sensors.
关键词： Double π-shaped resonator,Plasmonically induced transparency,Metamaterials,Terahertz
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - The Effects of Laser Polarization on The Performance of Terahertz Time-domain Spectrometer
摘要： A fiber-type terahertz time-domain spectrometer was designed by combining fiber femtosecond laser with fiber-coupled photoconductive antenna. The effects of laser polarization on the time-domain waveform, intensity and spectral characteristics are studied experimentally. By precise control and optimization of the polarization state of the femtosecond laser, the time-domain pulse splitting phenomenon is eliminated, and a single peak time-domain pulse with high signal-to-noise ratio is obtained.
关键词： Fiber,Polarization,Terahertz,Laser
更新于2025-09-16 10:30:52