分析了多量子阱材料各参数对其TE模和TM模有效折射率的影响。结果表明: 阱数增多, 多量子阱有效折射率降低, 当量子阱数目大于3时, 其有效折射率的变化不明显。垒厚增加, 有效折射率略有降低。存在合适的张应变量使TE模和TM模有效折射率峰值波长接近的同时, 折射率差值整体最小, 偏振相关性最小。据此提出多量子阱材料有效折射率低偏振相关设计方法, 并设计出C波段内(1530~1565nm)折射率低偏振相关的InGaAs/InGaAsP多量子阱材料。研究结果有助于设计实用化的有效折射率低偏振相关量子阱材料。
多量子阱 折射率偏振相关 量子阱数 垒厚 应变 multiple quantum well polarization dependence of refractive index number of quantum wells barrier thickness strain
分析了阱宽、垒高和应变对量子阱材料TE模和TM模折射率的影响, 并剖析了其中的物理机理。研究表明: 对于量子限制效应带来的量子阱折射率偏振相关性, 阱宽越小或垒高越高, 折射率偏振相关性越大。压应变增大时, 折射率偏振相关性增大, 张应变可以克服量子限制效应带来的折射率偏振影响。对于不同阱宽和垒高的量子阱, 均存在合适的张应变量使折射率偏振相关性最小, 且阱宽越小或垒高越高所需的张应变量越大。根据以上分析, 提出量子阱材料折射率低偏振相关设计方法, 并据此设计出C波段(1530~1565nm)内折射率低偏振相关(小于0.03)的量子阱材料In0.49Ga0.51As/In0.77Ga0.23As0.5P0.5。研究结果有助于优化设计光网络中关键器件。
量子阱 折射率偏振相关 阱宽 垒高 应变 quantum well polarization dependence of refractive index well width barrier height strain
对比分析了InGaAs/InGaAsP柱状量子点材料TE模和TM模增益谱及其折射率变化谱随点区材料组分、垒区材料组分和量子点高宽比的变化特性, 并剖析了其中的物理机理。进一步联合考虑点区和垒区组分变化对兼顾增益与折射率变化以及偏振相关性的影响, 提出了一种多参数调配方法, 并据此设计出在1550nm通信波段(1540~1560nm)内兼顾增益与折射率变化的低偏振量子点材料In0.97Ga0.03As/In0.76Ga0.24As0.52P0.48。最后通过分析, 选定合适的工作载流子浓度。当载流子浓度为0.6×1024 m-3时, TE模和TM模的3dB谱宽交叠区面积分别为8.66×103和7.55×103nm/cm, 增益和折射率变化的偏振相关性分别在3%和10%以内。研究结果有助于未来全光网络中关键器件的优化设计。
量子点 增益 折射率变化 3dB谱宽交叠区面积 低偏振相关 quantum dot gain refractive index change overlap region area of 3dB spectrum width low polarization dependence
Author Affiliations
Abstract
A new scheme to realize terahertz (THz) radiation generation, as well as high-speed THz modulation, for future high-speed THz communication systems, is proposed and discussed. The proposed experimental scheme includes two elemental parts: dual-wavelength mode-locking oscillating cavity and photomixing elements. The conditions for double-wavelength operation using the proposed experimental setup have been theoretically discussed and obtained. The mode-locked output optical short pulses with two highstability wavelengths are obtained and demonstrated. These can be used to produce THz radiation, as well as high-speed signal modulation, through the photomixing effects in an ultrafast oxygen-ion-implanted and epitaxial InGaAs:O for the future high-speed THz communication systems.
060.2390 Fiber optics, infrared 140.3520 Lasers, injection-locked 140.3560 Lasers, ring Chinese Optics Letters
2011, 9(s1): s10205
Author Affiliations
Abstract
Department of Optoelectronic Engineering, Huazhong University of Science and Technology, Wuhan 430074
An analytical equation, which directly relates amplified spontaneous emission (ASE) with small signal gain (SSG) of travelling-wave semiconductor optical amplifier (TWA), was derived. It was shown by theoretical analysis and experimental results that calibrated ASE spectra of TWA at different injection currents could be good evaluation and extension of SSG near gain peaks when gain peaks are larger than several decibels. The rapid evaluation method of SSG spectra is very simple, effective and especially applicable to batch measurement.
250.5980 semiconductor optical amplifiers 300.6170 spectra 230.7020 traveling-wave devices Chinese Optics Letters
2005, 3(8): 08483
