Superconductor insulator transition driven by pressure Abstract

  Roy Cohen  
Bar Ilan University

The Superconductor Insulator Transition (SIT) has been in the focus of condensed-matter research for the past few decades. The SIT is a quantum phase transition which occurs at zero temperature and is driven by quantum fluctuations and controlled by a non-thermal tuning parameter. Though the SIT has been extensively studied, some basic questions are still open, for example the nature of the insulating phase, the possible existence of an intermediate metal phase and more. So far, a few tuning parameters have been used to drive the transition, such as thickness, external magnetic field, and level of disorder. While these tuning parameters drive the system through the SIT, they do not allow direct comparison with theoretical models which are largely based on tuning the coupling between different superconducting sections of the system.

This proposal suggests a new direction to study this phenomenon and its characteristics by using a new tuning parameter – hydrostatic pressure. This is a clean parameter that effects the coupling between different localized regions and the density of state. We will explore the pressure induced superconductor-insulator-transition in different samples such as amorphous Indium Oxide films and 2D superconductor dot arrays and analyze the transition properties. This will be performed by using a diamond anvil cell, a device that can apply pressure on small samples up to 100 giga pascal. For this, we will develop a method to apply pressure on thin films by evaporating directly on a diamond.

We expect the results obtained in this work to provide important information about the physical processes in the heart of the superconductor insulator transition.