二维方形量子点体系等离激元的量子化

发布时间：2018-02-12 11:53

本文关键词： 二维方形量子点等离激元量子化　出处：《物理学报》2017年22期 　论文类型：期刊论文

【摘要】：量子点体系等离激元的研究是光电子学领域的热点.为进一步加深和完善对等离激元的量子效应的认识,本文利用紧束缚近似和线性响应理论研究了二维方形量子点体系对外场的集体响应.结果表明,当外场频率等于等离激元的频率时,量子点体系会有强烈的电荷振荡,并伴随着能量的极大吸收和近场的增强.在量子点中,等离子体存在分立的元激发.等离子体元激发的个数将随着量子点尺寸和电子个数的增加而增加.随量子点尺寸的增加,分立的等离激元将逐步呈现准连续的特性,即过渡为经典连续的等离激元,其频谱曲线演化为经典的色散曲线.结果还表明:随量子点尺寸的增加,等离激元的频率会红移,等离激元的激发强度会增大;随量子点中电子数的增加,等离激元的频率会蓝移,等离激元的激发强度会增大.
[Abstract]:The study of isopotons in quantum dot system is a hot topic in the field of optoelectronics. In this paper, the collective response of a two-dimensional square quantum dot system is studied by using the tight-binding approximation and the linear response theory. The results show that the quantum dot system has strong charge oscillation when the external field frequency is equal to the frequency of the constant exciton. Along with the maximum absorption of energy and the enhancement of near field, the plasma has discrete element excitation in quantum dot. The number of plasma element excitation will increase with the increase of quantum dot size and electron number, and with the increase of quantum dot size, the number of plasma element excitation will increase with the increase of quantum dot size. The discrete equipoliton will gradually present a quasi-continuous characteristic, that is, it will be transformed into a classical continuous equipoliton, and its spectrum curve will evolve into a classical dispersion curve. The results also show that the frequency of the equipoliton will shift red with the increase of the quantum dot size. With the increase of the number of electrons in the quantum dots, the frequency of the isophosphors will shift blue, and the excitation intensity of the isophosphors will increase with the increase of the number of electrons in the quantum dots.
【作者单位】：岭南师范学院物理科学与技术学院;西安航空学院电子工程学院;
【基金】：国家自然科学基金(批准号:11647156) 广东省自然科学基金(批准号:2014A030307035)资助的课题~~
【分类号】：O471.1

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