Emergent Quantum Phenomena in Moiré-Patterned TI/FM Heterostructures

The project will develop moiré-patterned superlattices in topological insulator/ferromagnet heterostructure using molecular beam epitaxy under ultrahigh vacuum to explore emergent quantum phenomena. By refining growth techniques, magnetic and non-magnetic layers will be integrated, employing advanced characterisation methods, including in-situ RHEED, X-ray reflectivity and diffraction, atomic force microscopy, low-temperature magnetic force microscopy, Raman spectroscopy, SQUID magnetometry, and magnetotransport measurements on Hall bar devices fabricated using lithography technique in the cleanroom.<br /> <br /> Crystalline solids disrupt translational symmetry, causing itinerant electrons in metals to form standing waves (Bloch states) through interference from periodic lattice potentials (Bragg reflection). This effect intensifies near Brillouin zone boundaries, producing van Hove singularities in the density of states (DOS) due to flat band formation. Modifying the Brillouin zone size offers a potential method to engineer DOS in crystalline materials.<br /> <br /> Moiré superlattices in graphene and transition metal dichalcogenides enable exploration of emergent quantum phenomena [1]. Periodic interlayer coupling in these structures creates long-wavelength modulations [2], effectively folding the Brillouin zone and introducing new DOS singularities. This project targets heterostructures of ultrathin topological insulators (e.g., Bi2Se3) and monolayer ferromagnetic materials (e.g., Fe3GeTe2 (FGT)) to investigate such properties.<br /> <br /> Topological insulators are promising for electronics, spintronics, and optics due to robust helical surface states that support low-dissipation spin currents and fast Dirac carrier dynamics. Ultrathin topological insulators suppress bulk contributions while preserving edge modes and inducing surface-state gaps via Dirac state hybridisation [3]. In ultrathin Bi2Se3/FGT heterostructure, magnetic proximity from FGT, with its out-of-plane magnetisation, can tune spin populations and generate chiral edge modes without external fields [4]. These modes may evolve into chiral Majorana states through coupling with s-wave superconductors.<br /> <br /> References<br /> 1. R. Bistritzer et al. PNAS 108, 12233 (2011)<br /> 2. R. Ryan et al. npj 2D Mater. Appl. 4, 33 (2020)<br /> 3. Y. Zhang et al. Nat. Phys. 6, 584 (2009)<br /> 4. Tokura et al., Nat. Rev. Phys. 1, 126 (2019)

<p>Formal applications for research degree study should be made online through the <a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University's website</a>. Please state clearly in the Planned Course of Study section that you are applying for <em><strong>PHD Physics & Astronomy FT,</strong></em>  in the research information section that the research degree you wish to be considered for is Emergent Quantum Phenomena in Moiré-Patterned TI/FM Heterostructures as well as <a href="https://eps.leeds.ac.uk/physics/staff/4131/dr-satoshi-sasaki?_gl=1*lgoozr*_gcl_au*NDIyMzgwMjgxLjE3NjM0MTMwNTE.*_ga*MTIzODQ2OTE0OC4xNzYzNDEzMDUx*_ga_SEKE21EBEQ*czE3NjYwOTkxNTYkbzckZzEkdDE3NjYwOTk5MTEkajQ3JGwwJGgxODcwNTA3ODc3">Dr Satoshi Sasaki</a> as your proposed supervisor and <em><strong>in the finance section, please state clearly the funding that you are applying for, if you are self-funding or externally sponsored.</strong></em></p> <p>Applications will be considered on an ongoing basis.  Potential applicants are strongly encouraged to contact the supervisors for an informal discussion before making a formal application.  We also advise that you apply at the earliest opportunity as the application and selection process may close early, should we receive a sufficient number of applications or that a suitable candidate is appointed.</p> <p><strong>If you are applying for University or School Scholarships for 2026/27 entry, with external sponsorship or you are funding your own study, please ensure you provide your supporting documents at the point you submit your application:</strong></p> <ul> <li>Full Transcripts of all degree study or if in final year of study, full transcripts to date including the grading scheme</li> <li>Personal Statement outlining your interest in the project</li> <li>CV</li> </ul> <p>If English is not your first language, you must provide evidence that you meet the University's minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p>

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in an appropriate discipline. The criteria for entry for some research degrees may be higher, for example, several faculties, also require a Masters degree. Applicants are advised to check with the relevant School prior to making an application. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<p><strong>Self-Funded or externally sponsored students are welcome to apply.</strong></p> <p><strong>Scholarship opportunities open from October 2025</strong></p> <p><strong>UK</strong> – The <a href="https://phd.leeds.ac.uk/funding/209-leeds-doctoral-scholarships-2024">Leeds Doctoral Scholarship</a> <strong>(closing date: 1 April 2026)</strong> and <a href="https://phd.leeds.ac.uk/funding/234-leeds-opportunity-research-scholarship-2022">Leeds Opportunity Research Scholarship</a> <strong>(closing date: 1 April 2026)</strong> are available to UK applicants.  <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Non-UK</strong> – The <a href="https://phd.leeds.ac.uk/funding/48-china-scholarship-council-university-of-leeds-scholarships-2026">China Scholarship Council-University of Leeds Scholarship</a> is available to nationals of China <strong>(closing date: 7 January 2026)</strong>. The <a href="https://phd.leeds.ac.uk/funding/73-leeds-marshall-scholarship">Leeds Marshall Scholarship</a> is available to support US citizens. <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p>Please note that if you are successful in securing an academic offer for PhD study, this does not mean that you have been successful in securing an offer of funding.</p> <p>If you are applying for the Leeds Doctoral Scholarship, Leeds Opportunity Research Scholarship, China Scholarship Council-University of Leeds Scholarship or Leeds Marshall Scholarship, you will need to complete a separate application, specific to these scholarships, to be considered for funding.</p> <p>You will be responsible for paying the overtime fee in full in your writing up/overtime year (£340 in Session 2025/26), but the scholarship maintenance allowance will continue to be paid for up to 6 months in the final year of award.</p> <p><strong>Important: </strong>Please note that that the award does <em><strong>not</strong></em> cover the costs associated with moving to the UK.  All such costs (<a href="https://www.leeds.ac.uk/international-visas-immigration/doc/applying-student-visa">visa, Immigration Health Surcharge</a>, flights etc) would have to be met by yourself, or you will need to find an alternative funding source. </p> <p>Please refer to the <a href="https://www.ukcisa.org.uk/">UKCISA</a> website for information regarding Fee Status for Non-UK Nationals.</p>

<p>For further information about your application, please contact PGR Admissions by email to <a href="mailto:phd@engineering.leeds.ac.uk">phd@engineering.leeds.ac.uk</a></p> <p>For further information about this project, please contact Dr Satoshi Sasaki by email to <a href="mailto:s.sasaki@leeds.ac.uk">S.Sasaki@leeds.ac.uk</a></p>