Condensed Atomic Molecular Physics (CAMP) Seminar

Condensed Atomic Molecular Physics (CAMP) Seminar

339 Davey Lab

2023-03-13

Speaker: Debanjan Chowdhury, Cornell Title: Useful Bounds on Superconducting Tc Abstract: Superconductivity in the limit of a vanishing bandwidth in isolated bands is a classic example of a non-perturbative problem, where BCS theory does not apply. What sets the superconducting phase stiffness, and relatedly the transition temperature, in this limit is of both fundamental and practical interest. This question has become especially relevant with the discovery of superconductivity in moiré materials. I will begin by examining critically the relevance of various proposed bounds on the superconducting transition temperature and propose a non-perturbative upper bound on the integrated optical spectral weight for partially filled electronic flat bands with generic density-density interactions. I will also present numerically exact results for the interplay between superconductivity and various competing orders in models of interacting flat-bands.

Schedule for Condensed Atomic Molecular Physics (CAMP) Seminar
Time	Speaker	Title
15:45	Debanjan Chowdhury	Useful Bounds on Superconducting Tc

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