Plasma waves in two-dimensional electron-hole system in gated graphene heterostructures
Plasma waves in two-dimensional electron-hole system in gated graphene heterostructures
复制标题
DOI：
10.1063/1.2426904
复制
发表时间：
2007-01
影响因子：
3.2
通讯作者：
V. Ryzhii;A. Satou;T. Otsuji
中科院分区：
文献类型：
--
作者：
V. Ryzhii;A. Satou;T. Otsuji
从理论上研究了高导电门控制的石墨烯基异质结中二维电子-空穴系统中的等离子体波。二维电子和空穴的能谱假定为锥形(类中微子)，即对应于它们的零有效质量。利用发展的模型，我们计算了等离子体波谱(电子和空穴密度以及自洽电势的时空变化)。我们发现，足够长的等离子体波呈现线性(类声音)色散，波速由栅层厚度、栅电压和温度决定。石墨烯异质结中的等离子体波速度可以大大超过常用的半导体门控异质结中的等离子体波速度。这种门控石墨烯异质结可用于利用等离子体波的不同电压可调太赫兹器件。
Plasma waves in the two-dimensional electron-hole system in a graphene-based heterostructure controlled by a highly conducting gate are studied theoretically. The energy spectra of two-dimensional electrons and holes are assumed to be conical (neutrinolike), i.e., corresponding to their zero effective masses. Using the developed model, we calculate the spectrum of plasma waves (spatio-temporal variations of the electron and hole densities and the self-consistent electric potential). We find that the sufficiently long plasma waves exhibit a linear (soundlike) dispersion, with the wave velocity determined by the gate layer thickness, the gate voltage, and the temperature. The plasma wave velocity in graphene heterostructures can significantly exceed the plasma wave velocity in the commonly employed semiconductor gated heterostructures. The gated graphene heterostructures can be used in different voltage tunable terahertz devices which utilize the plasma waves.