Department of Physics, University of Sargodha, Sargodha, Pakistan.
J Phys Condens Matter. 2011 Oct 26;23(42):425304. doi: 10.1088/0953-8984/23/42/425304.
In this work, we determine the effects of temperature on the magnetoplasmon spectrum of an electrically modulated graphene monolayer as well as a two-dimensional electron gas (2DEG). The intra-Landau band magnetoplasmon spectrum within the self-consistent field approach is investigated for both the aforementioned systems. Results obtained not only exhibit Shubnikov-de Haas (SdH) oscillations but also commensurability oscillations (Weiss oscillations). These oscillations are periodic as a function of inverse magnetic field. We find that both the magnetic oscillations, SdH and Weiss, have a greater amplitude and are more robust against temperature in graphene compared to a conventional 2DEG. Furthermore, there is a π phase shift between the magnetoplasmon oscillations in the two systems which can be attributed to Dirac electrons in graphene acquiring a Berry's phase as they traverse a closed path in a magnetic field.
在这项工作中，我们确定了温度对电调制石墨烯单层以及二维电子气（2DEG）的磁等离子体光谱的影响。我们针对上述两种系统，在自洽场方法中研究了内朗道带磁等离子体光谱。所得结果不仅表现出舒布尼科夫-德哈斯（Shubnikov-de Haas，SdH）振荡，还表现出合频振荡（Weiss 振荡）。这些振荡作为逆磁场的函数是周期性的。我们发现，与传统的 2DEG 相比，在石墨烯中，不仅磁振荡（SdH 和 Weiss）的幅度更大，而且对温度的鲁棒性更强。此外，两个系统中的磁等离子体振荡之间存在π相移，这可以归因于在磁场中穿过闭合路径时，石墨烯中的狄拉克电子获得了贝里相位。
