Dr. Sanjeev Kumar
Professor, Physical Sciences

Email sanjeev(AT)iisermohali.ac.in
Phone +91 172 2293133
Fax +91 172 2240266
Personal Page                                                               
Research Area
Condensed Matter Theory
Research Focus

My research focus is on theoretical and computational study of strongly interacting and disordered electron systems. Many of the transition-metal compounds belong to this catagory. Some examples are, the Cu-based high-Tc superconductors, the oxides of Mn, Co, Ni, etc., and the recently discovered Fe-based superconductors.

A microscopic understanding of the complex phenomena displayed by some of these systems is invariably obtained in terms of the relevant microscopic degrees of freedom, such as charge, spin and orbital. Taking into account the crystal structure, and the electronic structure at various levels of sophistication, one arrives at an effective Hamiltonian.Typically, such model Hamiltonians are rather complex with cross couplings between charge, spin, orbital and lattice variables. Moreover, the quantum many-body nature and the presence of disorder adds to the complexity.Therefore, to a large extent one has to rely on computational techniques to gain insight into the physics of such models.


Some of the topics that I am working on at present are:
(i)   topological magnetic textures in spin-orbit coupled systems
(ii)  ordering in low-dimentional frustrated quantum magnet
(iii) unconventional superconductivity in extended attractive Hubbard models.

Selected Publications
  • "Antiferromagnetic skyrmion crystals in the Rashba Hund’s insulator on triangular lattice" A Mukherjee, D Kathyat and S Kumar, Scientific Reports 11, 9566 (2021).
  • "Antiferromagnetic skyrmions and skyrmion density wave in a Rashba-coupled Hund insulator" A Mukherjee, D Kathyat and S Kumar, Phys. Rev. B 103, 134424 (2021).
  • "Electronic mechanism for nanoscale skyrmions and topological metals" D Kathyat, A Mukherjee and S Kumar, Physical Review B 103, 035111 (2021).
  • "Microscopic magnetic Hamiltonian for exotic spin textures in metals" D Kathyat, A Mukherjee and S Kumar, Physical Review B 102, 075106 (2020).
  • "Multiple phase transitions and high-field quadrupolar order in a model for β−TeVO4" A Singhania and S Kumar, Physical Review B 101, 064403 (2020).

Complete list of publications is available here - Google Scholar and Research Gate