We present a fast and robust method for the full-band solution of the Schrodinger equation on a grid, with the goal of achieving a more complete description of high energy states and realistic temperatures. Using fast Fourier transforms, the Schrodinger equation in the one band approximation can be expressed as an iterative eigenvalue problem for arbitrary shapes of the conduction band. The resulting eigenvalue problem can then be solved using Krylov subspace methods such as Arnoldi iteration. We demonstrate the algorithm by presenting an application, in which we compare nonparabolic effects in an ultrasmall metal-oxide-semiconductor (MOS) quantum cavity and a MOS quantum capacitor at room temperature. We show that for the cavity structure the nonparabolicity of the conduction band results in a significant lowering of high-energy electronic states and reshaping of the electron density, whereas the states and density in the MOS capacitor remain relatively unchanged.
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机译:我们提出了一种快速而稳健的方法,用于在网格上解薛定谔方程的全带,目的是实现对高能态和真实温度的更完整描述。使用快速傅里叶变换,单能带近似中的薛定谔方程可以表示为导带任意形状的迭代特征值问题。然后可以使用 Krylov 子空间方法(例如 Arnoldi 迭代)求解由此产生的特征值问题。我们通过展示一个应用来演示该算法,其中我们比较了室温下超小型金属氧化物半导体 (MOS) 量子腔和 MOS 量子电容器中的非抛物线效应。结果表明,对于空腔结构,导带的非副曲线性导致高能电子态显著降低和电子密度重塑,而MOS电容器中的态和密度保持相对不变。
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