可调谐垂直腔面发射激光器

近年来国内外在可调谐垂直腔面发射激光器这一研究领域取得了极大的进步。叙述了可调谐垂直腔面发射激光器的结构原理和发展历程,对不同结构的优缺点作了对比介绍,展望了可调谐激光器的发展前景。这种器件在光传输、光互连及光并行信息处理等方面有着良好的应用前景。     

垂直腔面发射激光器的温度特性研究

为了研究垂直腔面发射激光器（VCSEL）输出的光功率与器件温度的关系,确定用户可正常使用网络的温度范围,采用输出光功率与工作电流关系（P-I）模型进行了理论分析及实验验证,并通过简化模型参量及引入电压与电流关系（U-I）特性曲线来优化模型。采用了Levenberg-Marquardt（LM）算法来实现模型参量的求解,对比20℃下的测量数据与拟合数据的相似度,预测得到不同温度下的P-I特性曲线数据。结果表明,在固定温度下,输出光功率随着驱动电流的增加先增后减;在固定的驱动电流下,输出光功率随着温度增加而减小;要保证用户正常上网,电机房里VCSEL激光器工作的环境温度最多不能高于31℃。     

High-speed modulation characteristics of helium-implantedzinc-diffused vertical cavity surface emitting lasers

The high-speed modulation characteristics of helium-implanted zinc-diffused vertical cavity surface emitting semiconductor lasers are measured. Devices with a nominal active region diameter of 10 and 20 μm exhibit a move-out rate of 4.5-6.5 GHz/mW^1/2 and a K factor of 0.65-0.85 ns. Maximum modulation frequency is limited by ohmic heating to approximately 5.5 GHz for 10-μm diameter lasers and to 2.7 GHz for 20-μm diameter lasers. A rolloff in the response below the relaxation oscillation frequency is observed and is explained well by a diffusion capacitance model     

电泵浦垂直外腔面发射激光器振荡特性的理论分析及实验研究

对具有InGaAs/GaAsP量子阱周期增益结构有源区的980 nm电泵浦垂直外腔面发射激光器(EP-VECSEL)的振荡特性进行了理论分析及实验研究.模拟并分析了耦合腔条件下EP-VECSEL的振荡特性与其分布布拉格反射镜(DBR)及外腔镜反射率之间的关系,并根据理论分析结果对器件结构进行了优化设计.在实验上制备出具有不同外腔镜反射率的EP-VECSEL器件,并对其连续波(CW)振荡特性进行了研究.实验结果表明,有源区直径为300 μm的EP-VECSEL器件在外腔镜反射率为90 %时阈值电流为1.2 A,注入电流为4 A时连续激光输出功率为270 mW; 在外腔镜反射率为95%时阈值电流为0.9 A,4 A下输出激光功率为150 mW.实验结果与理论分析结论符合较好,说明本文采用的理论分析方法能有效模拟及优化EP-VECSEL器件的振荡特性.     

垂直腔表面发射激光器的研究

垂直腔表面发射激光器(VCSEL)是一种应用于光纤通信系统的低成本、高性能的特定波长光源,它具有测试简单、易耦舍以及易形成阵列等独特优势,已在光并行互连及高密度光存贮等领域得到大规模应用.文章介绍了VCSEL的结构和当前的制造工艺水平,阐述了各波段VCSEL的发展和应用现状,探讨了VCSEL在不同领域中的应用范围并指出了VCSEL的发展前景.     

长波长垂直腔面发射激光器

给出了长波长垂直腔面发射激光器的器件结构的发展现状，同时对GaInNAs／GaAs垂直腔面发射激光器进行了详细的介绍。最后，给出了所设计的新型1.3μm GaInNAs/GaAs长波长垂直外腔面发射半导体激光器的结构设计，有源区量子阱由980nm半导体激光二极管进行泵浦。这种器件设计实现了激光二极管泵浦与长波长垂直腔面发射激光器的有机结合，同时具有两者的优点。此外，本文还对器件的阈值特性和光输出功率进行了理论计算。     

Microchip vertical external cavity surface emitting lasers

Monolithic vertical external cavity surface emitting lasers of cavity mode volume <1 mm/sup 3/ have been fabricated in the 850 and 980 nm wavelength range. Pump-limited output power >350 mW in a TEM/sub 00/ mode was obtained at 850 nm. Output power >2.5 W was obtained at 980 nm.     

Variable reflectance vertical cavity surface emitting lasers

Singlemode operation in 850 nm vertical cavity surface emitting lasers is reported. The singlemode behaviour results from a radially-varying number of periods in the top distributed Bragg reflector mirror. At the centre of the device there are six additional quarter-wave layers (three periods) as compared to the edge. This provides higher mirror reflectivity to the fundamental mode without adding loss. Thus the top mirror geometry promotes singlemode operation of the laser from threshold to rollover     

Large CW power, very-low-threshold, single transverse modeoperation of vertical cavity mushroom structure surface emitting lasers

Summary form only given. Continuous-wave GaAs mushroom structure surface emitting laser (MSEL) operation at a threshold current as low as 1.6 mA, an output power >2.0 mW, and a single transverse mode up to three times threshold current is reported. The relatively large CW output power was achieved by reducing the series resistance using a selective zinc diffusion. The low threshold current and single-mode operation are attributed to good lateral current confinement in a small constricted region formed by mesa undercutting. The complete device was mounted junction-side up on a chip carrier and tested CW at room temperature. Some results are given     

Transverse mode selection with a passive antiguide region invertical cavity surface emitting lasers

We report a numerical analysis on the transverse mode behavior of a novel passive antiguide region buried heterostructure vertical cavity surface emitting laser, which emits a single stable transverse mode from a large aperture. Two- and three-dimensional beam propagation methods were used to calculate the threshold gains and the actual modal profiles for the fundamental and first order modes. We show that the passive antiguide structure is the main modal selection mechanism and the high order modes suffer much higher losses such that they are highly suppressed from reaching thresholds     

高功率980nm垂直腔面发射激光器的温度特性

应变补偿量子阱结构因带宽大、增益高和波长漂移速度低等特点而成为近年来研究的热点.首次介绍了国内980 nm 高功率InGaAs/GaAsP应变补偿量子阱结构的垂直腔面发射激光器(VCSEL) 变温实验,测得脉冲条件下600 μm直径的器件在10-100℃温度范围内发射波长漂移速度为0.05 nm/K,阈值电流随温度变化呈现先缓慢下降后迅速上升的特性.结合VCSEL反射谱、PL谱和增益峰值波长漂移速度,对器件阈值电流特性进行了合理的分析和解释.连续工作状态下,测试得到器件峰值功率为1 W,根据波长与耗散功率的实验曲线及热阻计算公式,可估算出垂直腔面发射激光器热阻值为10 K/W.     

Optically pumped blue-green vertical cavity surface emitting lasers

Optically pumped vertical cavity laser operation up to T=260K has been achieved in the 480-500 nm-wavelength range in ZnCdSe-ZnSSe-ZnMgSSe pseudomorphic separate confinement heterostructures, containing three active quantum well layers and dielectric high reflectivity mirrors     

Coupled-defect photonic crystal vertical cavity surface emitting lasers

Photonic crystal patterns containing two defects were fabricated within a large gain area in vertical cavity surface emitting lasers. By designing effective refractive index changes in the region between the defects through cavity shifts caused by photonic crystals, it was possible to coherently couple laser light output from the defects. This enables a novel way to fabricate coherently coupled laser arrays.     

The simulation of thermal characteristics of 980 nm vertical cavity surface emitting lasers

In order to design a single mode 980 nm vertical cavity surface emitting laser (VCSEL),a 2μm output aperture is designed to guarantee the single mode output.The effects of different mesa sizes on the lattice temperature,the output power and the voltage are simulated under the condition of continuous working at room temperature,to obtain the optimum process parameters of mesa.It is obtained by results of the crosslight simulation software that the sizes of mesa radius are between 9.5 to 12.5μm,which cannot only obtain the maximum output power,but also improve the heat dissipation of the device.     

Equivalent circuit for vertical cavity top surface emitting lasers

A small signal equivalent circuit for VCSELs is developed which provides an excellent fit to measured S-parameter data. Equivalent circuits were obtained for 6 mu m diameter, 780nm, gain guided VCSELs with 14GHz modulation bandwidth, the highest yet reported.<>     

Control of polarization switching in vertical coupled-cavities surface emitting lasers

We report a novel three-contact vertical-cavity surface-emitting laser (VCSEL) for use in polarization-sensitive optical applications. The device consists of two vertical cavities, coupled by a common mirror. We demonstrate that one can independently choose both the power of the output beam-through the current in the first cavity-and the polarization state-through the bias applied to the second cavity. The control of the polarization state is performed with a control voltage in the range -2 to 0 V. Within this interval, the structure exhibits a bistable behavior. We present the very first experimental proof of nonthermal, electrically induced polarization switching in coupled-cavities VCSELs.     

室温连续可见光垂直腔面发射激光器

利用钨丝掩膜质子轰击工艺制造出一种室温条件下可连续工作的可见光垂直腔面发射激光器。激射波长为６５０ｎｍ，未装在热沉上时连续工作最大输出功率为８５μＷ。     

Enhancement of spin information with vertical cavity surface emitting lasers

How the output polarisation of vertical cavity surface emitting lasers (VCSELs) can be controlled by the spin polarisation of the electrons in the active region is analysed. The main result is that a spin controlled VCSEL is feasible under realistic device conditions, i.e. at room temperature and for continuous wave operation.     

Influence of cavity tuning on the transverse mode invertical-cavity lasers

Data are presented showing the dependence of the transverse mode on the relative tuning of the cavity resonance to the gain peak in vertical-cavity surface-emitting lasers. Higher-order lasing modes are favored for the condition of a cavity resonant wavelength longer than that of the gain peak wavelength, while lower-order (single-lobed) radiation patterns are favored for the cavity resonance at a shorter wavelength than that of the gain peak