Controlling Emergent Orders in Quantum Materials

Lead Research Organisation: University of St Andrews
Department Name: Physics and Astronomy

Abstract

The properties of normal metals and insulators are quite well understood and numerical calculations of the electronic structures provide often astonishing precision, enabling a computational approach to designing materials with a specific property. This level of understanding has been instrumental in the development of semiconductor electronics. Quantum Materials exhibit a vast range of desirable properties, enabling new functionality, however these are usually unexpected and their properties cannot be predicted. Prime examples for the surprising properties of quantum materials are colossal magnetoresistance and high-temperature superconductivity. High temperature superconductivity occurs at temperatures of almost ten times higher than in conventional superconductors (except under pressure), whereas colossal magnetoresistance exhibits a change in resistivity with magnetic field which is orders of magnitude larger than for giant magnetoresistance, for the discovery of which the Nobel prize was awarded in 2007. Reaping the properties of quantum materials for applications has remained elusive, and a lack of understanding of their physics is a major obstacle to achieving this.
Reaping the properties of quantum materials for applications has remained elusive. The vast majority of our knowledge about the properties of these materials comes from bulk probes which have provided information about the exotic phases in these materials with exquisite detail. Yet for interfacing to the outside world, it is important to understand the impact of surfaces and interfaces on their emergent properties. The impact of these will provide new opportunities to control their properties, which might lead to entirely new functionalities. For emergent magnetic orders, our knowledge about the impact of the surface in these materials is currently practically zero, therefore this proposal aim to build unique new capability.
The here proposed research programme will address this, and lead to

(1) An understanding of the impact of surfaces and interfaces on emergent orders, which are critical to technological exploitation

(2) Development new methods for atomic scale imaging and characterization of magnetic structure and magnetic excitations

(3) Exploration of novel ways to control emergent magnetic states in reduced dimensionalities

This will be achieved through a multi-faceted approach combining methods which probe magnetic states at different depths from the surface, thereby enabling a complete characterization of the surface or interface impact on emergent magnetic states.

Planned Impact

The proposed research programme is primarily aimed at advancing the knowledge of humankind and further our understanding of nature and specifically the properties of materials. As such, there is no immediate direct economic benefit expected. However, there will be longer-term benefits from the knowledge generated in the course of this research programme.
Understanding quantum materials makes them possibly more amenable to optimize their properties for specific applications. Achieving this would have huge potential economic implications, as it might enable developing novel technologies based on quantum materials.
A large part of the proposed research will be carried out on custom built instrumentation. Existing connections to research-based companies will be strengthened to enable commercialization of instrumentation developed over the course of this research programme. This will likely be designs for advanced experimental tools such as microscope heads, low-noise designs for cryostats as well as control software developed for novel imaging modes or cryogenic electronics.
For highly developed countries like the UK and with diminishing natural resources, the education of the work force is the key economic factor to maintain competitiveness in an increasingly globalized environment. Beyond supplying professionals with relevant specialized skills, the research and training will supply the job market in the UK with highly trained and educated professionals with the skills to solve problems, think creatively and actively pursue challenging projects.
Results shall be published in high quality international journals, presented at international conferences, and, where appropriate, issued as press releases to the scientific media as well as posted on social media, ensuring maximal visibility and impact in the research community and for the general public.
To maximize impact in the scientific community as well as widen the base of academic beneficiaries', the investigators will organize two focused workshops surrounding the research proposed here. These workshops will serve to foster collaboration, identify future directions and discuss results from the research programme with the community.
To engage with the general public we will highlight the research at science fairs, as well as by publicizing our research through the websites of the investigators, as well as social media, media interviews, press releases and news items aimed at the general public.

Publications

10 25 50
 
Description Atomic-scale imaging of the superconducting condensate in the putative triplet superconductor Sr2RuO4: a platform for topological quantum computations?
Amount £12,000 (GBP)
Organisation Royal Society of Edinburgh (RSE) 
Sector Learned Society
Country United Kingdom
Start 01/2019 
End 12/2021
 
Description Research leave secondment for Chris Hooley at Rice University (January-April 2019) 
Organisation Rice University
Department Department of Physics and Astronomy
Country United States 
Sector Academic/University 
PI Contribution Chris Hooley visited Rice University, by invitation, for a four-month long Visiting Professorship from 7th January to 27th April 2019, to engage in collaborative work on the theory of non-Fermi-liquids and of the Kondo exhaustion phenomenon in heavy fermion materials.
Collaborator Contribution Rice University hosted Chris's visit, providing guest office accommodation, partial reimbursement of travel and accommodation expenses, and the time of their academic staff.
Impact No papers yet - partnership only began in late 2018.
Start Year 2018