近日，捷克查尔斯大学Martin Kozák团队研究了硅和金刚石的超快室温谷操纵。相关论文于2025年4月14日发表在《自然—物理学》杂志上。

一些半导体在其能带结构中具有多个导带简并最小值。如果有可能在它们的电子布居中产生差异，这些被称为谷的极小值可用于存储和处理信息。然而，为了与传统电子学竞争，有必要开发通用且快速的方法来控制和读取电子的谷量子数。尽管在具有破碎时间反转对称性的二维晶体中已经证明了对不等价谷中电子布居的选择性光学操纵，但在许多技术上重要的半导体材料中，包括硅和金刚石，都非常需要这种控制。

研究组展示了一种超快技术，用于在亚皮秒时间尺度上生成和读出体半导体中的谷极化电子群。该原理基于线性偏振红外飞秒脉冲振荡电场加速的电子的单向谷间散射。该研究结果推动了潜在谷电子器件的发展，此类器件可在室温下以太赫兹频率工作，并与现代硅基技术兼容。

附：英文原文

Title: Ultrafast room-temperature valley manipulation in silicon and diamond

Author: Gindl, Adam, mel, Martin, Trojnek, Frantiek, Mal, Petr, Kozk, Martin

Issue&Volume: 2025-04-14

Abstract: Some semiconductors have more than one degenerate minimum of the conduction band in their band structure. These minima—known as valleys—can be used for storing and processing information, if it is possible to generate a difference in their electron populations. However, to compete with conventional electronics, it is necessary to develop universal and fast methods for controlling and reading the valley quantum number of the electrons. Even though selective optical manipulation of electron populations in inequivalent valleys has been demonstrated in two-dimensional crystals with broken time-reversal symmetry, such control is highly desired in many technologically important semiconductor materials, including silicon and diamond. We demonstrate an ultrafast technique for the generation and read-out of a valley-polarized population of electrons in bulk semiconductors on subpicosecond timescales. The principle is based on the unidirectional intervalley scattering of electrons accelerated by an oscillating electric field of linearly polarized infrared femtosecond pulses. Our results are an advance in the development of potential room-temperature valleytronic devices operating at terahertz frequencies and compatible with contemporary silicon-based technology.

DOI: 10.1038/s41567-025-02862-4

Source: https://www.nature.com/articles/s41567-025-02862-4