Room-Temperature Spin-Transport Properties in an In0.5Ga0.5As Quantum Dot Spin-Polarized Light-Emitting Diode
Room-Temperature Spin-Transport Properties in an In0.5Ga0.5As Quantum Dot Spin-Polarized Light-Emitting Diode
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In0.5Ga0.5As 量子点自旋偏振发光二极管的室温自旋输运特性
DOI：
10.1103/physrevapplied.16.014034
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发表时间：
2021
影响因子：
4.6
通讯作者：
K. Sueoka and A. Murayama
中科院分区：
文献类型：
--
作者：
K. Etou;S. Hiura;S. Park;K. Sakamoto;J. Takayama;A. Subagyo;K. Sueoka and A. Murayama
了解半导体势垒中的自旋输运性质对于提高自旋偏振发光二极管（spin-polarized light-emitting diodes，简称spinLED）的性能是必不可少的，这将有助于未来光自旋电子学在信息处理中的集成。在这里，我们报告的温度和偏置电压的量子点（QD）自旋发光二极管的自旋输运性质的自旋依赖于使用的自旋相关的电致发光（EL）和时间分辨的光致发光的组合。当温度高于125 K时，量子点EL的自旋极化随着温度的升高而增加;这归因于量子点从电子自旋极化到光子圆极化的转换效率的提高。我们发现在200 K以上，电场和温度都能增强未掺杂势垒中的自旋弛豫。在298 K时，量子点电致发光的自旋极化降低到2.5 V以上，这是由于电子温度的升高引起的未掺杂势垒中D 'yakonovPerel'自旋弛豫的增强.这项研究提供了有价值的见解量子点自旋发光二极管在室温操作过程中的半导体势垒的自旋弛豫机制。
An understanding of the spin-transport properties in semiconductor barriers is essential to improve the performance of spin-polarized light-emitting diodes (spin LEDs) for future optospintronics integration in information processing. Here, we report on the temperature and bias-voltage dependence of spin-transport properties in anquantum dot (QD) spin LED using a combination of spin-dependent electroluminescence (EL) and time-resolved photoluminescence. The QD EL spin polarization increases with an increase in temperature above 125 K; this is attributed to the improved conversion efficiency from spin polarization of electrons to circular polarization of photons of the QDs. We find that both the electric field and temperature can enhance spin relaxation in the undopedbarrier above 200 K. At 298 K, the QD EL spin polarization decreases beyond 2.5 V; this is attributed to the enhanced D’yakonov Perel’ spin relaxation in the undopedbarrier caused by the increase in electron temperature. This study provides valuable insights into the spin-relaxation mechanism in the semiconductor barrier during the room-temperature operation of the QD spin LED.