Electric field control of magnetism in artificial multiferroics (SUSTech candidates only)


Please contact Dr Thomas Moore (Leeds) or Professor Lang Chen (SUSTech) to discuss this project further informally. 

Project description

Several routes to the electric field control of magnetism are currently being investigated: charge  modulation to manipulate the preferred direction of magnetization, ionic diffusion and strain coupling to piezoelectrics. A further possibility is to use exchange coupling between domains in ferroelectrics and ferromagnets. The electric field control of domain walls in an Fe film via  coupling to domains in a barium titanate (BTO) substrate has recently been demonstrated and may offer a route to low power memory/logic/sensor devices. However, ferromagnetic films such as Co/Pt with preferred direction of magnetization out-of-plane are more promising technologically because the domain walls are very narrow (a few nm wide) and furthermore the interfacial  Dzyaloshinskii-Moriya interaction can lead to nm-scale topologically stable skyrmion bubbles.

This project will investigate the coupling between ferroelectric materials and ferromagnetic layers with perpendicular anisotropy. Available ferroelectric crystals are lead-magnesium niobate-lead titanate (PMN-PT), lead zirconate titanate (PZT) and bismuth ferrite (BFO). The first task will be to obtain perpendicular anisotropy in the magnetic layer: the archetypal thin film is Co/Pt. We will then study the imprinting of ferroelectric domains into the ferromagnet using polarising and magneto-optical microscopy as well as scanning probe techniques. We shall investigate the response of the ferromagnet to electric-field reorientation of the ferroelectric polarisation and apply structural and magnetic characterisation methods including synchrotron techniques to  understand the interface physics.

Entry requirements

Applicants should have, or expect to obtain, a minimum of a UK upper second class honours degree in Physics or a related discipline, or equivalent.

How to apply

If English is not your first language, you must provide evidence that you have English language proficiency of at least IELTS 6.5 with no component below 6.0, or equivalent.

Applications should be submitted via SUSTech in the first instance. Following nomination by SUSTech, formal applications for Split-site research degree study should then be made online through the University of Leeds website. Please state clearly in the research information section that the PhD you wish to be considered for is ‘Electric field control of magnetism in artificial multiferroics (SUSTech candidates only)’ as well as Dr Thomas Moore as your proposed supervisor.

If you require any further information please contact the Graduate School Office e: physics.pg.admissions@leeds.ac.uk