DCMPMS Seminars

Designer quantum matter in van der Waals heterostructures

by Dr. Somesh C Ganguli (Aalto University, Finland)

Tuesday, May 17, 2022 from to (Asia/Kolkata)
at D 406Zoomlink https://zoom.us/j/95138152856
Description
In my talk, I will show the versatility of employing van der Waals (vdW) heterostructures to engineer  artificial electronic phenomena. The vdW systems has recently become de facto platform for the designer  materials for its extremely clean, defect-free and atomically well-defined interfaces. These factors make it  possible to combine materials with seemingly competing electronic orders such as ferromagnetism,  superconductivity. 

In the first part of my talk, I will describe the fabrication of designer 2-dimensional topological  superconductor having 1-dimensional Majorana edge modes by combining 2D ferromagnet, namely  monolayer CrBr3 and s-wave superconductor NbSe2 [1]. I will also demonstrate how the Moire′ pattern between CrBr3 and NbSe2 modulates the topological band structure [2]. 

In the second part of my talk, I will demonstrate that Kondo coupling between 2 different geometrical  phases of TaS2, namely 1T-TaS2 having localized magnetic moments and 1H-TaS2 having itinerant  conduction electrons generates artificial heavy fermion system [3] which mimics the behavior of  compounds containing rare-earth elements with 4f or 5f electrons. 

Finally, I will talk about the signatures of unconventional superconductivity in monolayer transition metal  dichalcogenide superconductors 1H-NbSe2 [4] and 1H-TaS2 [5] demonstrating the role of the  dimensionality and confinement in realizing unconventional superconductivity in vdW systems.