- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Numerical simulation on terahertz wave propagation in plasma channels
摘要： Terahertz (THz) wave generated by femtosecond laser ?lamentation can spatially constrained inside the plasma channels. Our simulation results show that this constraint to THz wave will gradually weaken with the increasing THz frequency. At the same time, results also indicate that the higher plasma density possesses the stronger constraint. In addition, the model ?eld radius and width of THz wave will become larger with the increasing plasma channel radius. Based on the simulation results we ?nd the changes of refractive index at THz wave play an important role on THz wave propagation in plasma channels.
关键词： Plasma channel,Waveguiding,Terahertz wave propagation
更新于2025-09-23 15:23:52
-
Investigating flexible band-stop metamaterial filter over THz
摘要： Metamaterial filter is a novel type of photoelectric device. In this study, a triple-band band-stop filter for terahertz is fabricated by magnetron sputtering of periodic metamaterial resonators on flexible polyimide substrates. The band-stop resonant points of the filter are 107.3, 167.45, and 209.9 GHz, and the 3 dB bandwidths are 14.13, 14.03, and 22.44 GHz. S21 parameters at the resonance point reach ?30.217, ?30.432, and ?38.618 dB, thereby possibly achieving an excellent frequency blocking performance. Simultaneously, the stop-band can be adjusted by controlling the length of the metamaterial unit size, thus modifying the frequency of the filter.
关键词： Terahertz wave,Photoelectric device,Band-stop filter,Metamaterials
更新于2025-09-23 15:23:52
-
[IEEE 2019 4th International Conference on Power and Renewable Energy (ICPRE) - Chengdu, China (2019.9.21-2019.9.23)] 2019 4th International Conference on Power and Renewable Energy (ICPRE) - Laser Beam Path Control Using a PSD Fuzzy Controller
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2025-09-23 15:21:01
-
Simultaneous generation of two THz waves with bulk LiNbO3 and four THz waves with PPLN by coupled optical parametric generation
摘要： We present a theoretical research concerning simultaneous generation of two terahertz (THz) waves with bulk LiNbO3 and four THz waves with periodically poled LiNbO3 (PPLN) by coupled optical parametric generation (COPG). First, we investigate collinear phase matching of COPG generating two orthogonally polarized THz waves with two types of phase matching of o = e ? e and o = e ? o with bulk LiNbO3. The two orthogonally polarized THz waves are generated from stimulated polariton scattering (SPS) with A1 and E symmetric transverse optical (TO) modes in bulk LiNbO3, respectively. Then, we ?nd that perturbations of phase mismatch for o = e ? e and o = e ? o can be compensated by a same grating vector of PPLN. As a result, four THz waves are simultaneously generated with a PPLN crystal and a pump laser. We calculate third-order nonlinear optical coef?cients of o = e ? o generating THz waves from E symmetric TO modes. The intensities of four THz waves are calculated by solving coupled-wave equations. The calculation results demonstrate that four THz waves with high intensities can be simultaneously realized by COPG with existing laser technology and crystal fabrication technology.
关键词： Stimulated polariton scattering,Coupled optical parametric generation,Periodically poled LiNbO3,Terahertz wave
更新于2025-09-23 15:21:01
-
A flexible and ultra-broadband terahertz wave absorber based on graphenea??vertically aligned carbon nanotube hybrids
摘要： Electromagnetic wave absorbers are essential devices in imaging, wireless communication and energy harvesting systems. In this paper, we propose and experimentally demonstrate a flexible and ultra-broadband terahertz (THz) wave absorber based on graphene-vertically aligned carbon nanotube (G-VACNT) hybrids. The THz absorber consists of Cu/PDMS/graphene/VACNT functional layers on PET substrate. Measured results show a 100% qualified operating bandwidth (i.e., absorptance >0.9) and an average power absorptance of 0.986 within the 0.2-3.0 THz range. The absorber also exhibits good absorption performances for a wide range of incident angles up to 60°, and can function normally in different bending states due to its excellent flexibility. The incoming energy of THz waves absorbed by the G-VACNT hybrids results in a temperature increase whose spatial distribution is corresponding to the profile of incident THz beam, providing an efficient and low cost approach for THz beam profiling, collimation and focusing. This work paves the way for the development of large-scale and broadband THz wave absorbers.
关键词： Vertically aligned carbon nanotube,Ultra-broadband,Graphene,Flexible,Terahertz wave absorber
更新于2025-09-23 15:19:57
-
Ultrahigh Q-factor dual-band terahertz perfect absorber with dielectric grating slit waveguide for sensing
摘要： Terahertz (THz) perfect absorber with ultra-narrow bandwidth at near-unity absorbance has been a challenging issue due to mutual restriction of elemental requirements in design. Here, we propose an extremely sharp dual-band THz perfect absorber with ultrahigh Q-factor and near-unity absorbance by incorporating a Fabry-Perot micro-cavity into dielectric grating slit waveguide. Full-wave simulation demonstrates that the proposed structure not only achieves ultra-narrow band perfect absorption with an ultrahigh Q-factor of 4600 in THz regime, but also shows extraordinary sensing performance with a record figure of merit (FOM) of 2415 at THz frequencies. The optimized guided mode resonance leads to the ultrahigh Q-factor through suppressing the absorption and radiation losses. The enhanced interaction between the cavity localized fields and the analytes significantly improves THz sensing capability. Our design approach shows a promising future in simple and inexpensive THz biochemical sensors.
关键词： THz sensing,Terahertz wave,perfect absorber,ultrahigh Q-factor
更新于2025-09-19 17:13:59
-
240 Gbit/s Silicon Photonic Mach-Zehnder Modulator Enabled by Two 2.3-Vpp Drivers
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
-
[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
-
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
-
[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