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arXiv · 1312.6669

Shape Resonances in superconducting gaps in a 2DEG at oxide-oxide interface

Antonio Bianconi·Davide Innocenti·Antonio Valletta·Andrea Perali
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Abstract

In multiband superconductivity, the case where the single electron hopping between different Fermi surface spots of different symmetry is forbidden by selection rules is recently attracting a large interest. The focus is addressed to superconductivity made of multiple condensates with different symmetry where the chemical potential crosses a 2.5 Lifshitz transition. This can now be investigated experimentally by fine-tuning of the chemical potential in the range of tens meV around a band edge using gate voltage control. We discuss here the case of the two-dimensional electron gas (2DEG), at the interface between two insulating oxides confined within a slab of 5 nanometers thickness, where the electronic structure is made of subbands generated by quantum size effects. We focus on the case of the BCS-BEC transition in the upper subband for different pairing strength in the shallow Fermi surface.

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Antonio Bianconi, Davide Innocenti, Antonio Valletta, Andrea Perali. 2013-12-23. Shape Resonances in superconducting gaps in a 2DEG at oxide-oxide interface. https://doi.org/10.1088/1742-6596/529/1/012007

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