Our group has identified, using low temperature STM and infrared spectroscopy measurements, the structure and composition of the hydrocarbon contamination found on many van der Waals material surfaces (hBN, MoS2, etc.). When exposing fresh surfaces to ambient conditions, the initial contamination layer is replaced within days by a monolayer of straight chain alkanes. These alkanes […]
Our STM measurements reveal a degenerate many-body ground state in the flat band of rhombohedral graphite. The system at charge neutrality is possibly the simplest crystal hosting quantum magnetism, forming a new experimental platform to study strongly correlated electrons.
Using scanning tunneling microscopy (STM) measurements, we have observed the closing of the topological gap in the van der Waals material ZrTe5, by applying mechanical deformations to it in the form of bubbles.
The result of our collaboration with the group of Prof. Yanpeng Qi at ShanghaiTech University has just been published in npj Quantum Materials. Our work reveals that Pt2HgSe3 (jacutingaite) transforms to a monoclinic structure (space group Pc), above 55 GPa and at the same time becomes a superconductor.
In our recent paper published in Nature Nanotechnology, we show that the plasmon frequencies of graphene can be tuned from terahertz frequencies into the visible range. This enables extremely sensitive detection of molecules from femtomolar concentrations by Raman spectroscopy.
Pt2HgSe3 is a layered, van der Waals mineral, called jacutingaite. It was discovered in 2008 in Brazil  and the monolayer has been predicted to be a large gap topological insulator . Our group has been able to detect signatures of the predicted topological edge states, within a bulk gap that is larger than 100 […]
Our paper on intra-valley scattering on strain-induced pseudo-magnetic field fluctuations has been published. Kun, P. et al. Large intravalley scattering due to pseudo-magnetic fields in crumpled graphene. npj 2D Mater. Appl. 3, 11 (2019).