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arXiv · 2106.09446

Direct detection of odd-frequency superconductivity via time- and angle-resolved photoelectron fluctuation spectroscopy

Viktoriia Kornich·Frank Schlawin·Michael A. Sentef·Björn Trauzettel
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Abstract

We propose a measurement scheme to directly detect odd-frequency superconductivity via time- and angle-resolved photoelectron fluctuation spectroscopy. The scheme includes two consecutive, non-overlapping probe pulses applied to a superconducting sample. The photoemitted electrons are collected in a momentum-resolved fashion. Correlations between signals with opposite momenta are analyzed. Remarkably, these correlations are directly proportional to the absolute square of the time-ordered anomalous Green's function of the superconductor. This setup allows for the direct detection of the "hidden order parameter" of odd-frequency pairing. We illustrate this general scheme by analyzing the signal for the prototypical case of a two-band superconductor.

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Viktoriia Kornich, Frank Schlawin, Michael A. Sentef, Björn Trauzettel. 2021-06-17. Direct detection of odd-frequency superconductivity via time- and angle-resolved photoelectron fluctuation spectroscopy. https://doi.org/10.1103/physrevresearch.3.l042034

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