Single-shot real-time sub-nanosecond electron imaging aided by compressed sensing: Analytical modeling and simulation. (February 2019)

• Record Type: Journal Article
• Authors: Liu, Xianglei; Zhang, Shian; Yurtsever, Aycan; Liang, Jinyang
• Is Part Of: Micron. Volume 117(2019)
• Page Start: 47
• Page End: 54
• Publication Date: 2019-02
• Subjects: Transmission electron microscopy -- Ultrafast imaging -- Compressed sensing -- Streak imaging; Microscopy -- Periodicals; Electron Probe Microanalysis -- Periodicals; Microscopy -- Periodicals; Microscopie -- Périodiques; Microscopy; Periodicals; 502.82
• DOI: 10.1016/j.micron.2018.11.003
• Languages: English
• ISSNs: 0968-4328

Abstract

Highlights: We propose two configurations that enable single-shot real-time ultrafast electron imaging in the sub-nanosecond temporal regime. We outline the design of compressed-sensing-aided ultrafast imaging modalities in transmission electron microscopy. We establish a procedure through simulation for examining and optimizing each operation in the data acquisition process. We demonstrat the feasibility of proposed configurations in simulation by image reconstruction using experimentally acquired data. Abstract: Bringing ultrafast (nanosecond and below) temporal resolution to transmission electron microscopy (TEM) has historically been challenging. Despite significant recent progress in this direction, it remains difficult to achieve sub-nanosecond temporal resolution with a single electron pulse, in real-time (i.e., duration in which the event occurs) imaging. To address this limitation, here, we propose a methodology that combines laser-assisted TEM with computational imaging methodologies based on compressed sensing (CS). In this technique, a two-dimensional (2D) transient event [i.e. ( x, y ) frames that vary in time] is recorded through a CS paradigm, which consists of spatial encoding, temporal shearing via streaking, and spatiotemporal integration of an electron pulse. The 2D image generated on a camera is used to reconstruct the datacube of the ultrafast event, with two spatial and one temporal dimensions, via a CS-based image reconstruction algorithm. Using numerical simulation, we find that the reconstructed results are in good agreement with the ground truth, which demonstrates the applicability of CS-based computational imaging methodologies to laser-assisted TEM. Our proposed method, complementing the existing ultrafast stroboscopic and nanosecond single-shot techniques, opens up the possibility for single-shot, real-time, spatiotemporal imaging of irreversible structural phenomena with sub-nanosecond temporal resolution.