Electrically controlled quantum transition to an anomalous metal in 2D

Abstract

The mechanism through which superconductivity is destroyed upon controlled disordering often holds the key to understanding the mechanism of emergence of superconductivity. Here we demonstrate an $in$-$situ$ mechanism to control the fraction of disorder in a 2D superconductor. By controlling an electric field V${}_G$, we created an assembly of segregated superconducting nano-islands and varied the inter-island distance to accomplish a quantum phase transition from a superconducting phase to a strange quantum anomalous metallic (QAM) phase at LaVO${}_3$/SrTiO${}_3$ interfaces. In the QAM phase, the resistivity dropped below a critical temperature (T${}_{CM}$) as if the system was approaching superconductivity, and then saturated, indicating the destruction of global phase coherence and the emergence of a phase where metal-like transport of Bosons (a Bose metal) becomes a possibility. The unprecedented control over the island size is obtained through the control of nanometer scale ferroelectric domains formed in the SrTiO${}_3$ side of the interface due to a low-temperature structural phase transition.

To be published in ACS Applied Electronic Materials

References in corpus (4)

• Disorder-Induced Inhomogeneities of the Superconducting State Close to the Superconductor-Insulator Transition
• Gate-Tunable Negative Longitudinal Magnetoresistance in the Predicted Type-II Weyl Semimetal WTe2
• Polar Discontinuity Doping of the LaVO_3/SrTiO_3 Interface
• Quantum breakdown of superconductivity in low-dimensional materials