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arXiv · 1509.00871

Attosecond Quantum-Beat Spectroscopy in Helium

Niranjan Shivaram·Xiao-Min Tong·Henry Timmers·Arvinder Sandhu
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Abstract

The evolution of electron wavepackets determines the course of many physical and chemical phenomena and attosecond spectroscopy aims to measure and control such dynamics in real-time. Here, we investigate radial electron wavepacket motion in Helium by using an XUV attosecond pulse train to prepare a coherent superposition of excited states and a delayed femtosecond IR pulse to ionize them. Quantum beat signals observed in the high resolution photoelectron spectrogram allow us to follow the field-free evolution of the bound electron wavepacket and determine the time-dependent ionization dynamics of the low-lying 2p state.

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Niranjan Shivaram, Xiao-Min Tong, Henry Timmers, Arvinder Sandhu. 2015-09-02. Attosecond Quantum-Beat Spectroscopy in Helium. https://arxiv.org/abs/1509.00871

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