排序方式: 共有90条查询结果,搜索用时 31 毫秒
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STRUCTURE STUDY OF MODULATION-DOPED Cd1-xMnxTe: In/CdTe STRAINED LAYER MULTIPLE QUANTUM WELLS 下载免费PDF全文
The photomodulated reflectivity (PR) spectroscopy of modulation-doped diluted mag-netic semiconductor Cd1-xMnxTe: In/CdTe multiple quantum wells has been measured at 20-300K. Several spectral features associated with intersubband transitions have been found. The band structure of Cd1-xMnxTe: In/CdTe has been calculated by the Hartree self-consistent method. The results show that the theory is in agreement with experiments. In addition, an abnormal transition intensity ratio of 22H (the second heavy hole subband to the second electroa subband) to 11H (the first heavy hole subband to the first electron subband) caused by electron filled effect has been reported. At low temperature, a feature associated with Fermi level is observed, which has not been reported before. 相似文献
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本文通过电调制反射谱(ER)、光调制反射谱(PR)、荧光光谱(PL)以及吸收光谱首次对导电聚合物聚三甲基噻吩(P3MT)进行综合光谱测量,并根据准一维导电体系的元激发态理论模型对实验结果作了分析,研究结果表明,导电聚合物P3MT的禁带宽度约为2eV,在70—300K的温度范围内对温度不敏感;掺杂和光照皆可诱导产生本征元激发态双极化子;离化杂质对双极化子有“钉扎效应”;光照可产生显著的激子态,本文还就P3MT中光电子交换微观过程的物理图象作了讨论。 相似文献
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本文讨论了用光学方法研究杂质诱发定域化振动模的理论模型,分门别类地论述了半导体中杂质诱发的定域模、禁带模、共振模和准定域模晶格振动及非晶态半导体的晶格振动谱,给出了它们的综合结果。半导体中杂质诱发定域模已被人们广为研究,作者主要以自己的结果阐述了禁带模、共振模、准定域模和非晶态半导体振动谱研究在近年来取得的重要进展。除以较多篇幅研究各种定域化振动模的位置外,本文还从键—电荷模型出发讨论了杂质诱发振动吸收带的强度。 相似文献
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在室温下用显微光致发光的方法对单根V形GaAs/AlGaAs量子线进行了沿垂直于量子线方向的 空间分辨扫描测试,观察到各种量子结构的光致发光谱随空间位置的变化.在量子线区域附 近观察到来自量子线(QWR)、颈部量子阱(NQWL)和垂直量子阱(VQWL)等各种结构的发光,而 在距离量子线约1μm以远的发光光谱表现出侧面量子阱(SQWL)的发光.对全部发光光谱用高 斯线形进行了拟合,发现QWR和SQWL的发光包含了两个荧光峰,将它们分别归诸为电子到轻 、重空穴的跃迁.拟合后发光强度的空间变化直接确定了与量子线
关键词:
V形GaAs/AlGaAs量子线
显微光致发光
空间分辨扫描 相似文献
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用红外反射光谱的方法对生长在蓝宝石衬底上的α-GaN外延薄膜的载流子浓度和迁移率进行了研究.通过测量蓝宝石衬底和不同Si掺杂浓度的一系列GaN外延膜的远红外反射谱并进行理论计算和拟合,得到GaN中的声子振动参量和等离子振荡的频率及阻尼常量,并由此计算得到其载流子浓度和迁移率.计算结果,红外方法得到的载流子浓度与Hall测量相一致,但迁移率比Hall迁移率要低约二分之一.同时红外谱与喇曼谱上明显观察到LO声子与等离子体激元耦合模,(LPP)随掺杂浓度的变化.
关键词:
α-GaN外延薄膜
红外反射光谱
载流子浓度
迁移率
LO声子与等离子体激元耦合模
Raman光谱 相似文献
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The photoconductivity spectra of semimagnetic semiconductor Cd0.7Mn0.3Se have been measured at 50-300 K and in the wavelength range of 5500 ? to 8000 ?. It is found that the energy gap of Cd0.7Mn0.3Se changes with the temperature linearly, and the temperature coefficient (dEg/dT) is about -7×10-4 eV/K. A photoconductivity peak which is related to Mn2+ is also found. This peak is located around 1.85 eV, nearly unshifted with variation of the temperature. The possible transition mechanisms in Cd1-xMnxSe have been discussed in the light of group theory and crystal field theory, and the results are in good agreement with experiments. 相似文献