Noise in a Two Dimensional Electron Gas

这个项目的主要目标是研究在强电场存在下，即当电子与晶格失去平衡时，二维电子气的噪声特性。这个话题很重要，因为噪声定义了半导体器件的灵敏度和可靠性。这些器件的小型化将导致对2-D而不是3-D电子气的重视。在本工作中，我们将使用玻耳兹曼输运方程和蒙特卡罗方法来模拟二维电子气中的电流涨落(噪声)。通过计算电流-电流相关函数的时间相关性，可以确定电流波动及其频率相关性。噪声由散射过程定义。我们将研究局域声子和界面声子对噪声的贡献。将特别注意背景和远距离电离杂质的电势散射。我们将研究这些杂质态的捕获和随后的释放；我们预计这些过程将对高电场区域的噪声做出重大(通常是压倒性的)贡献。重点将放在优化2-D结构的低噪声配置上。

The main goal of this project is to investigate the noise characteristics of a two-dimensional (2-D) electron gas in the presence of a strong electric field , i.e., when electrons are out of equilibrium with the lattice. This topic is important because noise defines the sensitivity and reliability of semiconductor devices. The miniaturization of these devices will lead to an emphasis on 2-D as opposed to 3-D electron gas. In the present work we will use the Boltzmann transport equation and the Monte Carlo method to simulate current fluctuation (noise) in a 2-D electron gas. By calculating the time dependence of the current- current correlation function it is possible to determine the current fluctuation and its frequency dependence. Noise is defined by scattering processes. We will study the contribution of localized and interface phonons to the noise. Special attention will be paid to scattering by the electric potential of background and remote ionized impurities. Capture by these impurity states and subsequent release will be examined; we expect that these processes will make major (and often overwhelming) contributions to noise in the high electric field region. Emphasis will be placed on the optimization of low-noise configurations for 2-D structures.