Quantum Spin Systems and Magnetic Frustration Investigated with High Frequency AC Susceptibility and Muons
Lead Research Organisation:
CARDIFF UNIVERSITY
Department Name: School of Physics and Astronomy
Abstract
The study of fundamental properties of magnetic materials constantly evolves resulting in the observation of exciting new physical behaviour. This project will involve the study of geometrically frustrated materials, where magnetic interactions cannot be satisfied on a lattice leading to more than one ground state, a so called degenerate state. The work is an exciting area of condensed matter physics because excitations out of the ground state can reveal behaviour such as the observation of magnetic monopoles in the frustrated
material spin ice and because some ground states are always fluctuating because the quantum interactions become dominant. The large number of papers in Nature and Science in recent years demonstrate the vitality of this research area.
This project will involve looking at dynamics of frustrated systems showing quantum behaviour, using a unique high frequency susceptometer and a superconducting quantum interference device developed in Cardiff at temperatures below 1 K. You will learnt the art of low temperature techniques, a highly desired skill in the drive for superconducting qubits. The work will be supported using complimentary techniques such as muons which are atomic probes of spin dynamics. Experimental work will be performed in Cardiff on
our state of the art dilution fridge system and susceptometer, and at muon facilities in both Switzerland and Oxford. You will have the opportunity to travel to international conferences to present your work as well as publishing your work. This combination of techniques is available in only a few places in the world and will enable you to understand complex behaviour of frustrated materials.
material spin ice and because some ground states are always fluctuating because the quantum interactions become dominant. The large number of papers in Nature and Science in recent years demonstrate the vitality of this research area.
This project will involve looking at dynamics of frustrated systems showing quantum behaviour, using a unique high frequency susceptometer and a superconducting quantum interference device developed in Cardiff at temperatures below 1 K. You will learnt the art of low temperature techniques, a highly desired skill in the drive for superconducting qubits. The work will be supported using complimentary techniques such as muons which are atomic probes of spin dynamics. Experimental work will be performed in Cardiff on
our state of the art dilution fridge system and susceptometer, and at muon facilities in both Switzerland and Oxford. You will have the opportunity to travel to international conferences to present your work as well as publishing your work. This combination of techniques is available in only a few places in the world and will enable you to understand complex behaviour of frustrated materials.
Organisations
People |
ORCID iD |
Sean Richard Giblin (Primary Supervisor) | |
Edward Riordan (Student) |
Publications
Chen H
(2020)
Tuning the dynamics in Fe3O4 nanoparticles for hyperthermia optimization
in Applied Physics Letters
Gao S
(2018)
Dipolar Spin Ice States with a Fast Monopole Hopping Rate in CdEr_{2}X_{4} (X=Se, S).
in Physical review letters
Riordan E
(2019)
Design and implementation of a low temperature, inductance based high frequency alternating current susceptometer.
in The Review of scientific instruments
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
EP/N509449/1 | 30/09/2016 | 29/09/2021 | |||
1797796 | Studentship | EP/N509449/1 | 30/09/2016 | 29/06/2020 | Edward Riordan |
Description | A new device capable of measuring high frequency magnetic properties of samples at very low temperatures has been designed and implemented. A paper about the device has been published and results using it have also been published in another paper. Measurements have also been performed on magnetic nanoparticles using the device which may have some medical applications. Two recently discovered frustrated magnetic materials have been studied in depth and some unexpected behaviour explored. The unexpected behaviour has been investigated with several techniques, which have narrowed down the possible origin but a single cause is not yet obvious, studies are ongoing. Other measurements on other frustrated materials have also been performed. An experiment to manipulate a quantum state has been performed in two materials and was successful. Code has been written in python to simulate the experiment and quantify the results. |
Exploitation Route | High frequency device may have applications in other areas of magnetism as well as possible biomedical applications. ac susceptibility is a common technique for the characterisation of magnetic materials, extending the frequency range over which it can be applied can be useful in many applications. Results in frustrated magnetic materials will have relevance to further study of the field. The observed phenomenon is expected to exist in other materials with similar properties but is as yet unobserved. If it is observed this work will be beneficial to their study. Study of entanglement in muon fluorine states may have applications to further muon studies in fluorinated materials as well as potential quantum computing applications, this area of research is still ongoing. |
Sectors | Other |