丁香园AV

Synopsis

Strontium titanate is a remarkable material:   it is a low-carrier-density superconductor that shows evidence of pre-formed pairs well above Tc; it is a quantum paraelectric, with a ferroelectric transition that is suppressed by quantum fluctuations; and it was recently shown to host a two-dimensional electron liquid (2DEL) at interfaces with a wide variety of polar perovskite materials.  In this talk, I will discuss how quantum paraelectricity afffects the structure of the 2DEL.  Based on a theoretical model of an ideal SrTiO3 interface, I will show that proximity to a ferroelectric quantum critical point leads to universal tails in the electron density.  These results are interesting as a novel manifestation of quantum criticality, but also have implications for the temperature and gate-voltage dependence of interface transport properties.