Research interests of Professor Bansil have focused on questions concerning the electronic structure and spectroscopy of high-Tc superconductors, topological insulators, nanosystems, and other complex materials. Professor Bansil’s group has developed and implemented the theoretical methodology for carrying out first-principles calculations of spectral intensities relevant for angle-resolved photoemission, scanning tunneling microscopy/spectroscopy, inelastic x-ray scattering, magnetic and non-magnetic Compton scattering, positron-annihilation angular correlation, among other spectroscopies in systems of the complexity of the high-Tc’s. Theoretical approaches based on the local-density approximation as well as techniques for going beyond this framework to incorporate effects such as strong electron correlations, superconductivity and phonons have been developed to obtain comprehensive spectroscopic modeling schemes. We are also considering how effects of substitutions and dopants on the electronic states can be treated realistically in wide classes of materials. These investigations have yielded, for example, important new insights into the existence of Fermi surfaces, the nature of electronic states near the Fermi energy, as well as the mechanism of superconductivity in the high-Tc’s. We have predicted successfully many new topological insulator and topological semimetal materials through first-principles modeling. Professor Bansil’s research effort involves extensive collaborations with groups within and outside the United States.
Selected Publications (from a total of 370)
A. Bansil, H. Lin, T. Das: “Topological Band Theory,” Colloquium: Reviews of Modern Physics 88, 021004 (2016).
G. Chang, et al.: “A strongly robust type II Weyl fermion semimetal state in Ta3S2,” Science Advances 2, e1600295 (2016).
M. Neupane, et al.: “Observation of spin-polarized surface state in a noncentrosymmetric superconductor BiPd,” Nature Communications 7, 13315 (2016).
Y. Feng, et al.: “Direct Evidence of Interaction-Induced Dirac Cones in Monolayer Silicene/Ag(111),” Proceedings National Academy of Sciences 113, 1180 (2016).
T-R. Chang, et al.: “Prediction of an arc-tunable Weyl Fermion metallic state in MoxW1−xTe2,” Nature Communications 7, 10639 (2016).
W. Shi, et al.: “Ligand-surface interactions and surface oxidation of colloidal PbSe quantum dots revealed by thin-film positron annihilation methods,” Applied Physics Letters 108, 081602 (2016).
H. Hafiz, et al.: “Visualizing redox orbitals and their potentials in advanced lithium-ion battery materials using high-resolution x-ray Compton scattering,” Science Advances 3, e1700971(2017).
S-Y. Xu, et al.: “Discovery of Lorentz-violating type II Weyl fermions in LaAlGe,” Science Advances 3, e1603266 (2017).
Y. Okada, et al.: “Quasiparticle Interference on Cubic Perovskite Oxide Surfaces,” Physical Review Letters 119, 086801 (2017).
A. Vargas, et al.: “Tunable and laser-reconfigurable 2D heterocrystals obtained by epitaxial stacking of crystallographically incommensurate Bi2Se3 and MoS2 atomic layers,” Science Advances 3, e1601741 (2017).