We are investigating low dimensional correlated electron materials and devices using primarily scanning probe microscopy and spectroscopy. Topics of interest include charge and orbital order, superconductivity, topology and synthetic 2D devices.
In the following, you can find more information about ongoing scientific projects.
This chemically versatile family of two-dimensional materials spans the entire range of electronic structures, from insulator to metal, and hosts a number of interesting properties such as charge density wave modulations, orbital ordering and superconductivity. These materials are the subject of intense studies both in bulk and exfoliated few layer forms. We focus on the charge-ordered and superconducting phases in bulk compounds.
Similarly to graphene, transition metal dichalcogenides can be exfoliated down to single layers. We exploit this to our advantage to investigate the thickness dependence of their electronic properties down to the single layer limit. The local nature of scanning probes enables us to characterize different thicknesses locally in a single experiment by measuring successive terraces on a unique exfoliated crystal.
Scanning tunneling microscopy and spectroscopy are techniques of choice to characterize high temperature superconductors. Imaging can resolve charge ordered phases in real space, and spectroscopy gives access to key features in the local density of states with high spatial resolution, such as the electronic vortex core structure and spatial inhomogeneities of the superconducting ground state.
STM of synthetic 2D devices
We use dry transfer method to assemble thin exfoliated flakes into two-dimensional heterostructure devices and investigate their properties by scanning tunneling microscopy and spectroscopy. Properties of interest include proximity induced spin orbit coupling, new electronic structures induced by Moiré superlattices, and gate tunable ground states (charge order and superconductivity, for example).