PhD Studentship: In-situ gating and strain-tuning of electronic properties of correlated oxide heterostructures [STU0445]

Website DiamondLightSou Diamond Light Source

Supervisors: Dr Tien-Lin Lee from Diamond Light Source Ltd and Prof Ralph Claessen and Prof. Michael Sing from University of Wuerzburg (Germany)

Project description:

Unlike conventional semiconductors or band insulators, many 3d, 4d and 5d transition metal oxides (TMOs) are found to deviate from a simple band structure description due to the presence of electron correlation, which arises from Coulomb repulsion between electrons. Depending on the filling and width of the d band, these oxides can be tuned to be either a correlated metals or a (Mott) insulator, making them prominent members of the family of quantum materials and promising candidates for novel nanoelectronic applications. Understanding and controlling the crossover between the states in these systems has been at the heart of modern condensed matter physics.

In this study, a collaboration between Beamline I09 at Diamond Light Source and Prof. Ralph Claessen’s group at University of Wuerzburg, we will investigate the electronic properties of correlated oxide heterostructures that are tuned in-situ to the vicinity of a metal-insulator transition (MIT). Our study will focus on two TMO thin films: SrVO3 and SrIrO3, which are a 3d correlated metal and a 5d semimetal, respectively, in the bulk but turn insulating when becoming thinner than a few unit cells. The aim is to characterise how their fundamental properties such as charge carrier density, mass renormalisation and correlation strength evolve as the systems are driven across their electronic phase boundaries. The external stimulus that drives the MIT will explore the charge degree of freedom via gate-voltage control and the lattice degree of freedom via strain control.

The study will involve pulsed laser deposition and pre-characterisation of thin film samples at University of Wuerzburg and in-situ gating and strain-tuning experiments at at I09 exploiting soft x-ray angle-resolved photoemission spectroscopy (SX-ARPES), hard x-ray photoelectron spectroscopy (HAXPES) and x-ray absorption spectroscopy (XAS). Applicants are expected to have a good understanding of solid-state physics and be motivated to develop advanced experimental skills.

Diamond Light Source Ltd holds an Athena SWAN Bronze Award, demonstrating their commitment to provide equal opportunities and to advance the representation of women in STEM/M subjects: science, technology, engineering, mathematics and medicine.

Applications are now open. For more information on the project and how to apply, visit the ad on the universities website.

To apply for this job please visit www.physik.uni-wuerzburg.de.