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arXiv · 2001.09891

Accessing the spectral function in a current-carrying device

Davide Curcio·Alfred J. H. Jones·Ryan Muzzio·Klara Volckaert·Deepnarayan Biswas·Charlotte E. Sanders·Pavel Dudin·Cephise Cacho·Simranjeet Singh·Kenji Watanabe·Takashi Taniguchi·Jill A. Miwa·Jyoti Katoch·Søren Ulstrup·Philip Hofmann
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Abstract

The presence of an electrical transport current in a material is one of the simplest and most important realisations of non-equilibrium physics. The current density breaks the crystalline symmetry and can give rise to dramatic phenomena, such as sliding charge density waves [1], insulator-to-metal transitions [2,3] or gap openings in topologically protected states [4]. Almost nothing is known about how a current influences the electron spectral function, which characterizes most of the solid's electronic, optical and chemical properties. Here we show that angle-resolved photoemission spectroscopy with a nano-scale light spot (nanoARPES) provides not only a wealth of information on local equilibrium properties, but also opens the possibility to access the local non-equilibrium spectral function in the presence of a transport current. Unifying spectroscopic and transport measurements in this way allows non-invasive local measurements of the composition, structure, many-body effects and carrier mobility in the presence of high current densities.

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Davide Curcio, Alfred J. H. Jones, Ryan Muzzio, Klara Volckaert, Deepnarayan Biswas, Charlotte E. Sanders, Pavel Dudin, Cephise Cacho, Simranjeet Singh, Kenji Watanabe, Takashi Taniguchi, Jill A. Miwa, Jyoti Katoch, Søren Ulstrup, Philip Hofmann. 2020-01-27. Accessing the spectral function in a current-carrying device. https://doi.org/10.1103/physrevlett.125.236403

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