Configurational electronic states in layered transition metal dichalcogenides

Jaka Vodeb

Complex Matter Department, Jožef Stefan Institute

Abstract:

I will present my doctoral thesis, where we first address the problem of metastable mesoscopic configurational charge ordering in TMDs with a sparsely filled charged lattice gas model in which electrons are subject only to screened Coulomb repulsion. The model correctly predicts commensurate CDW states corresponding to different transition metal dichalcogenides at magic filling fractions fm=1/3,1/4,1/9,1/13,1,16 . Doping away from fm  results either in multiple near degenerate configurational states, or an amorphous state at the correct density observed by scanning tunneling microscopy. Quantum fluctuations between degenerate states predict a quantum charge liquid at low temperatures, revealing a new generalized viewpoint on both regular, irregular, and amorphous charge ordering in transition metal dichalcogenides.

During the development of our model, we also found it useful in three other examples of experiments. The first application of the model deals with theoretical modeling of the non-equilibrium amorphous state in 1T-TaS₂. The second application deals with quantum billiards of correlated electrons confined in triangular transition metal dichalcogenide monolayer nanostructures created by laser quench. The third and last application of our model deals with a time-domain phase diagram of metastable states in a charge-ordered quantum material. Finally, we extend our classical version of the model to the quantum regime and deploy it on D-Wave’s quantum computer. We explore the observation of quantum domain melting and its simulation with a quantum computer.

The seminar will take place in the F7 Seminar Room and via Zoom. The details for connecting to the meeting can be found below:

Join Zoom Meeting

https://zoom.us/j/97046995988?pwd=NDBKVDFyVzgzb3NWbk5Ra0NGbkEzQT09

Meeting ID: 970 4699 5988
Passcode: 851027

Link to previous seminars:

http://www-f7.ijs.si/archives/

Calendar of upcoming seminars