Impact of Built-In Electric Field on the Emission Characteristics of InAs/GaAs Quantum Dot Laser Structure,Physica Status Solidi (B) - Basic Solid State Physics

当前位置： X-MOL 学术 › Phys. Status Solidi B › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Impact of Built-In Electric Field on the Emission Characteristics of InAs/GaAs Quantum Dot Laser Structure
Physica Status Solidi (B) - Basic Solid State Physics ( IF 1.5 ) Pub Date : 2021-05-06 , DOI: 10.1002/pssb.202100090
Nitika Gupta ₁ , Priyabrata Mudi _{2,

3} , Arvind Yelashetty ₁ , Tarun K. Sharma _{2,

3} , Devnath Dhirhe ₁

Affiliation

The impact of the built-in electric field on the emission characteristics of an InAs/GaAs quantum dot (QD) laser structure is investigated by performing systematic spectroscopic measurements. Photoluminescence (PL) features related to the ground state (GS) and excited state (ES) transitions of a QD ensemble are clearly observed in the temperature range of 8–300 K. The cross-sectional transmission electron microscopy image and a systematic analysis of temperature-dependent PL data confirm the excellent crystalline and optical quality of the QD laser structure. It is found that the values of the activation energy associated with GS and ES transitions of the QD sample reasonably match with the energy splitting of PL features. This successfully explains the trends observed in temperature-dependent PL spectra, where thermal transfer of carriers to the wetting/barrier layer via QD excited states is proposed to be a major decay channel. An interesting observation is made where the integrated intensity of PL features increases up to 75 K and falls thereafter during the heating cycle. Such a peak-like behavior of the integrated intensity is explained by invoking the temperature dependence of the built-in electric field, which is estimated from the analysis of Franz–Keldysh oscillations observed in photoreflectance spectra and is important in the design of QD lasers.

中文翻译：

内置电场对InAs/GaAs量子点激光器结构发射特性的影响

通过执行系统的光谱测量，研究了内置电场对 InAs/GaAs 量子点 (QD) 激光器结构发射特性的影响。在 8-300 K 的温度范围内可以清楚地观察到与 QD 系综的基态 (GS) 和激发态 (ES) 跃迁相关的光致发光 (PL) 特征。横截面透射电子显微镜图像和系统分析与温度相关的 PL 数据证实了 QD 激光器结构的出色晶体和光学质量。发现与 QD 样品的 GS 和 ES 跃迁相关的活化能值与 PL 特征的能量分裂合理匹配。这成功地解释了在温度相关 PL 光谱中观察到的趋势，其中载流子通过 QD 激发态到润湿/阻挡层的热转移被认为是主要的衰变通道。一个有趣的观察是 PL 特征的积分强度增加到 75 K，然后在加热循环中下降。积分强度的这种峰状行为可以通过调用内置电场的温度依赖性来解释，这是根据对光反射光谱中观察到的 Franz-Keldysh 振荡的分析估计的，并且在 QD 激光器的设计中很重要。

更新日期：2021-07-12

点击分享查看原文

点击收藏

阅读更多本刊最新论文