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The 2022 recruitment round for PhD positions is open!

PhD positions are available, funded through a number of routes, including through EPSRC DTG places and an International Max Planck Research School. You can find a list of example projects on the web page of the School of Physics and Astronomy.
Our group develops and operates cutting edge instrumentation for atomic scale studies of electronic structure, complex magnetic orders and unconventional superconductivity in quantum materials. The experiments are undertaken in dedicated ultra-low vibration labs. Projects are embedded in the Centre for Designer Quantum Materials, offering a vibrant and stimulating environment.

If you have any questions, do not hesitate to get in touch. Submit applications through the University portal.

In a new paper in npj Quantum Materials we show how small rotations of the ruthenium oxide octahedra in the enigmatic superconductor Sr₂RuO₄ enable us to detect its van Hove singularity, which would otherwise be practically invisible for us due to its orbital character. Modelling of the quasiparticle interference shows excellent agreement with experiment once the rotation of the octahedra is accounted for, resulting in chiral scattering patterns around defects.

Analogous to Magellan’s circumnavigation of the earth enabling him to deduce information about the shape of the earth in 3D from its surface, read our new paper in Nature Communications to find out how we can use 2D quasi-particle interference at the surface of a rock to infer information about its 3D electronic structure.

Read our new paper in Physical Review Letters to find out how one can use helium to measure exchange interactions between a sample and the tip of a Scanning Tunneling Microscope. We show that helium becomes trapped in the tunneling junction, but can be ejected by the tunneling electrons enabling us to spatially map its binding energy. Alternative title could have been ‘how a helium leak enabled us to probe exchange interactions’.

Meet members of the group and hear about our most recent results in the following talks and posters at the virtual meeting of the condensed matter section of the DPG (27 September – 1 October 2021, see here for a list of our contributions, note that times are CEST (UTC+2)):

• Christopher Trainer on Monday, 27.9., 10:30, talk MA 1.2: The effect of trapped Helium atoms on spin polarized tunneling in an STM tunnel junction
• Olivia Armitage on Tuesday, 28.9., 10:30, talk MA 4.2: Spin-polarised imaging and quasi-particle interference of the van-der-Waals ferromagnet Fe₃GeTe₂
• Izidor Benedičič on Tuesday, 28.9., 13:30, poster TT 9.27: Anisotropic metamagnetism in trilayer ruthenate Sr₄Ru₃O₁₀
• Carolina Marques on Thursday, 30.9., 12:15, talk TT 19.5: Nematicity and checkerboard order in the surface layer of Sr₂RuO₄

In addition, Andreas Kreisel from University of Leipzig will talk about our joint work on Sr₂RuO₄ on Thursday, 30.9., 12:30, in talk TT 19.6 on Quasiparticle Interference of the van-Hove singularity in Sr₂RuO₄.

Our paper on magnetic-field tunable van-Hove singularities in Sr₂RuO₄ featured on the back cover of Advanced Materials. The image shows the structure of the van-Hove singularity and the two order parameters required to obtain it, nematicity and checkerboard charge order.

Read more in the original reference: Magnetic-Field Tunable Intertwined Checkerboard Charge Order and Nematicity in the Surface Layer of Sr₂RuO₄, 2021, 32, 2100593.

Cover image © Wiley-VCH GmbH. Reproduced with permission.

Do you think STM is only a surface-sensitive probe? Read Christopher’s new preprint where we show magnetostriction measurements done in our vector-field STM and use it to map out the phase diagram of CeSb₂. An exciting way to directly link bulk properties to the surface electronic structure.

What has Händel’s Passacaglia to do with electron correlations? Find out more about the aesthetics of emergent phenomena from Carolina’s talk in the Nottingham Prize Competition at the Physical Electronics Conference 2021. Click 👍 if you like it!

Image: Chi Ming Yim

Our paper on strain-stabilized (π,π) order at the surface of FeTe has appeared in Nano Letters (here), showing how in samples under uniaxial strain a new surface phase emerges, showing (π,π) charge order with only short-ranged magnetic order instead of the usual (π,0) magnetic order of FeTe.

Meet us at the APS march meeting and learn more about our research. You can see members of the group and our research at the following contributions:

• Wednesday, March 17, 2021, 10:48–11:00: Soumendra Panja: “Tuning the ground state of iron based superconductors by uniaxial strain”
• Wednesday, March 17, 2021, 16:36-16:48: Chi-Ming Yim: “Strain-tuning emergent phases in FeTe between (π,0) and (π,π) order”
• Thursday, March 18, 2021, 8:00–8:12: Carolina Marques: “Checkerboard charge order, nematicity and magnetic-field tuning of a van Hove singularity in the surface layer of Sr₂RuO₄“
• Thursday, March 18, 2021, 12:06–12:42: Luke Rhodes: “Understanding the nematic electronic structure of FeSe and its impact on the superconducting state”