We present exact results that give insight into how interactions lead to transport and superconductivity in a flat band where the electrons have no kinetic energy. We obtain bounds for the optical spectral weight for flatband superconductors that lead to upper bounds for the superfluid stiffness and the twodimensional (2D)
Using polarized optical and magnetooptical spectroscopy, we have demonstrated universal aspects of electrodynamics associated with Dirac nodal lines that are found in several classes of unconventional intermetallic compounds. We investigated anisotropic electrodynamics of
 Publication Date:
 NSFPAR ID:
 10081684
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 116
 Issue:
 4
 Page Range or eLocationID:
 p. 11681173
 ISSN:
 00278424
 Publisher:
 Proceedings of the National Academy of Sciences
 Sponsoring Org:
 National Science Foundation
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