Virtual Mobility Grant UAM (Spain), U. Central (Colombia), U. De los Andes (Colombia), Ames Laboratory (USA) and U. Grenoble Alpes (France)

The main aim of the proposal was to study in Madrid samples provided by collaborators from France, Colombia and the United States.  In this regard, thanks to the VM grand the local team has maintained a significant remote activity to screen samples, prepare these with the geometry needed for the experiments in Madrid, discuss the starting hypothesis and addressed preliminary results and best measurement strategy to address these results.

The VM grant allowed reinforcing the collaboration between expert researchers in the grown of high-quality single crystals of the heavy-fermion compounds. The group from Grenoble sent to Madrid different batches of the heavy-fermions Ce(Ru_0.92Rh_0.08)₂Si₂ and the Lanthanum doped La-CeRu₂Si₂. The last compound was measured by a master student under the supervision of the young researcher proponent of this VM Grant.

In the same way, the VM grant intensified the collaboration with researchers from Colombia, which lead to publications recently [see for example: Physical Review Research 2, 013125 (2020), Communications Physics 1, 30 (2018)]. We are now working on high-quality samples of TaTe₄ synthesized by the group of Colombia.

Thanks to the collaboration with P.C. Canfield, which has lead to numerous publications, we synthesized AuSn4, a superconducting compound candidate to host topological properties. An undergraduate student, under the supervision of the young researcher of the VM proposal, made the first tunneling spectroscopy studies in the superconducting phase of this compound. There is one publication in preparation. We show in the figure the superconducting density of states vs temperature in this compound.

All the meetings to share and discuss the experimental results, the theoretical analysis, and the scientific reports were performed by using the virtual platforms Zoom.