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Interface-mediated pairing in field effect devices

V. Koerting·Qingshan Yuan·P. J. Hirschfeld·T. Kopp·J. Mannhart
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Abstract

We consider the pairing induced in a strictly 2D electron gas (2DEG) by a proximate insulating film with polarizable localized excitations. Within a model of interacting 2D electrons and localized two-level systems, we calculate the critical temperature $T_c$ as a function of applied voltage and for different materials properties. Assuming that a sufficient carrier density can be induced in a field-gated device, we argue that superconductivity may be observable in such systems. $T_c$ is found to be a nonmonotonic function of both electric field and the excitation energy of the two-level systems.

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V. Koerting, Qingshan Yuan, P. J. Hirschfeld, T. Kopp, J. Mannhart. 2007-01-15. Interface-mediated pairing in field effect devices. https://doi.org/10.1103/physrevb.71.104510

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