{"title":"Transient drift velocity of photoexcited electrons in CdTe","authors":"Dongfeng Liu","doi":"10.1007/s10825-024-02165-6","DOIUrl":null,"url":null,"abstract":"<div><p>The relaxation dynamics of photoexcited carriers of CdTe is vital toward its applications in high-performance optoelectrical devices. In this paper, the dependences of transient drift velocities of photoexcited electrons in bulk CdTe on photoexcitation conditions such as the pump intensity and photoexcitation wavelengths, temperature and externally applied electric field, are systematically investigated by the ensemble Monte Carlo method (EMC). The main scattering mechanisms including nonelastic deformation potential acoustic phonon, deformation potential optical phonon scattering, ionized impurity (II) scattering, and polar optical phonon scattering events, the effects of nonequilibrium phonons, and the Pauli exclusion principle are considered in EMC. The velocity overshoot phenomenon is only found to arise at a low temperature (100 K), with a longer photoexcitation wavelength (640 nm) and under a higher electric field (> 50 kV/cm). The effect of nonequilibrium phonons on electron drift velocity is found to be dependent on the photoexcited carrier density. Our findings may be useful for designing novel CdTe-based optoelectronic devices, which employ nonequilibrium photoexcited carriers to improve the performance.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"23 3","pages":"498 - 506"},"PeriodicalIF":2.2000,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Computational Electronics","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10825-024-02165-6","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
The relaxation dynamics of photoexcited carriers of CdTe is vital toward its applications in high-performance optoelectrical devices. In this paper, the dependences of transient drift velocities of photoexcited electrons in bulk CdTe on photoexcitation conditions such as the pump intensity and photoexcitation wavelengths, temperature and externally applied electric field, are systematically investigated by the ensemble Monte Carlo method (EMC). The main scattering mechanisms including nonelastic deformation potential acoustic phonon, deformation potential optical phonon scattering, ionized impurity (II) scattering, and polar optical phonon scattering events, the effects of nonequilibrium phonons, and the Pauli exclusion principle are considered in EMC. The velocity overshoot phenomenon is only found to arise at a low temperature (100 K), with a longer photoexcitation wavelength (640 nm) and under a higher electric field (> 50 kV/cm). The effect of nonequilibrium phonons on electron drift velocity is found to be dependent on the photoexcited carrier density. Our findings may be useful for designing novel CdTe-based optoelectronic devices, which employ nonequilibrium photoexcited carriers to improve the performance.
期刊介绍:
he Journal of Computational Electronics brings together research on all aspects of modeling and simulation of modern electronics. This includes optical, electronic, mechanical, and quantum mechanical aspects, as well as research on the underlying mathematical algorithms and computational details. The related areas of energy conversion/storage and of molecular and biological systems, in which the thrust is on the charge transport, electronic, mechanical, and optical properties, are also covered.
In particular, we encourage manuscripts dealing with device simulation; with optical and optoelectronic systems and photonics; with energy storage (e.g. batteries, fuel cells) and harvesting (e.g. photovoltaic), with simulation of circuits, VLSI layout, logic and architecture (based on, for example, CMOS devices, quantum-cellular automata, QBITs, or single-electron transistors); with electromagnetic simulations (such as microwave electronics and components); or with molecular and biological systems. However, in all these cases, the submitted manuscripts should explicitly address the electronic properties of the relevant systems, materials, or devices and/or present novel contributions to the physical models, computational strategies, or numerical algorithms.