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All-optical control and visualization of ultrafast two-dimensional atomic motions in a single crystal of bismuth

ABSTRACT: In a bulk solid, optical control of atomic motion provides a better understanding of its physical properties and functionalities. Such studies would benefit from active control and visualization of atomic motions in arbitrary directions, yet, so far, mostly only one-dimensional control has been shown. Here we demonstrate a novel method to optically control and visualize two-dimensional atomic motions in a bulk solid. We use a femtosecond laser pulse to coherently superpose two orthogonal atomic motions in crystalline bismuth. The relative amplitudes of those two motions are manipulated by modulating the intensity profile of the laser pulse, and these controlled motions are quantitatively visualized by density functional theory calculations. Our control-visualization scheme is based on the simple, robust and universal concept that in any physical system, two-dimensional particle motion is decomposed into two orthogonal one-dimensional motions, and thus it is applicable to a variety of condensed matter systems. Controlling the motion of atoms in solids with light allows for a deeper understanding of their fundamental properties, yet most studies only deal with one spatial dimension. Katsuki et al. extend this approach to two-dimensional control and use it to visualize atomic motion in bismuth.

SUBMITTER: Katsuki H

PROVIDER: S-EPMC3868158 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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