1.4k citations · 2.9k across the 51 of their papers we have counts for
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Quantized two terminal conductance, edge states and current patterns in an open geometry 2-dimensional Chern insulator
Junaid Majeed Bhat, R. Shankar, Abhishek Dhar
The quantization of the two terminal conductance in 2D topological systems is justified by the Landauer-Buttiker (LB) theory that assumes perfect point contacts between single chan…
Coulomb interactions, Dirac sea polarization and symmetry breaking of the integer quantum Hall states of graphene
Vinu Lukose, R. Shankar
We investigate effects of the filled Dirac sea on the symmetry breaking in the integer quantum Hall states of graphene with long-ranged Coulomb interactions. Our model also…
Topological Surface States and Dirac point tuning in ternary Bi2Te2Se class of topological insulators
M. Neupane, S. -Y. Xu, L. A. Wray +14
Using angle-resolved photoemission spectroscopy, we report electronic structure for representative members of ternary topological insulators. We show that several members of this f…
A semi-classical analysis of Dirac fermions in 2+1 dimensions
Moitri Maiti, R. Shankar
We investigate the semiclassical dynamics of massless Dirac fermions in 2+1 dimensions in the presence of external electromagnetic fields. By generalizing the matrices to the s…
Effects of iron doping on the topological insulator surfaces
L. A. Wray, Y. Xia, S. -Y. Xu +5
Topological insulators embody a newly discovered state of matter characterized by conducting spin-momentum locked surface states that span the bulk band gap. So far, most of the st…
Observation of Topological Order in the TlBiSe2 class : Probing the "spin" and "phase" on topological insulator surfaces
Su-Yang Xu, L. A. Wray, Y. Xia +9
A topological insulator is characterized by spin-momentum locking on its boundary. The spin momentum locking on the surface of a three dimensional topological insulator leads to th…
Discovery of several large families of Topological Insulator classes with backscattering-suppressed spin-polarized single-Dirac-cone on the surface
Su-Yang Xu, L. A. Wray, Y. Xia +9
Three dimensional (3D) topological insulators are novel states of quantum matter that feature spin-momentum locked helical Dirac fermions on their surfaces and hold promise to open…
Topological Control: Systematic control of topological insulator Dirac fermion density on the surface of Bi2Te3
Y. Xia, D. Qian, D. Hsieh +8
Three dimensional (3D) topological insulators are quantum materials with a spin-orbit induced bulk insulating gap that exhibit quantum-Hall-like phenomena in the absence of applied…
Exact Haldane mapping for all and super universality in spin chains
A. M. M. Pruisken, R. Shankar, N. Surendran
The low energy dynamics of the anti-ferromagnetic Heisenberg spin chain in the semiclassical limit is known to map onto the O(3) nonlinear model with a ter…
Symmetry breaking by the sea of Dirac-Landau levels in graphene
Vinu Lukose, R. Shankar
The quantum Hall states of graphene have a filled Dirac sea of Landau levels. The short ranged SU(4) symmetry breaking interactions can induce a staggered polarization of the sea o…
Hamiltonian theory of the half-filled Landau level with disorder: Application to recent NMR data
Ganpathy Murthy, R. Shankar
The Hamiltonian Theory of the fractional quantum Hall effect is an operator description that subsumes many properties of Composite Fermions, applies to gapped and gapless cases, an…
Novel electric field effects on Landau levels in Graphene
Vinu Lukose, R. Shankar, G. Baskaran
A single graphene layer exhibits an anomalous Landau level spectrum. A massless Dirac like low energy electronic spectrum underlies this anomaly. We study, analytically and numeric…
Massless excitations at in the model with large values of
A. M. M. Pruisken, I. S. Burmistrov, R. Shankar
We study the instanton vacuum of the model with large values of in 1+1 space-time dimensions. Unlike the longstanding claims which state that the theory always has a…
The renormalization group for interacting fermions: from Fermi liquids to quantum dots
R. Shankar
The renormalization group approach as developed by the author for Fermi liquids is applied to clean Fermi liquids and ballistic quantum dots. In the former case Landau theory is sh…
Quantum Hall Skyrmion Lattices at
Sumithra Sankararaman, R. Shankar
We investigate the classical ground state configurations of a collection of skyrmions in the limit of vanishing Lánde factor. We show that in this limit, the skyrmions which ar…
Spiral orientational order in quantum Hall skyrmion lattices
Sumithra Sankararaman, R. Shankar
We investigate the existence of spiral ordering in the planar spin orientation of skyrmions localised on a face centered rectangular lattice (FCRL). We use the non-linear sigma mod…
Luttinger revisted-the renormalization group approach
R. Shankar
Luttinger's contributions abound in different parts of many-body physics. Here I review the ones that appear when one uses the Renormalization Group (RG) to study the subject: the…
Hamiltonian theory of gaps, masses and polarization in quantum Hall states: full disclosure
R. Shankar
I furnish details of the hamiltonian theory of the FQHE developed with Murthy for the infrared, which I subsequently extended to all distances and apply it to Jain fractions ν= p/(…
Scaling Relations for Gaps in Fractional Quantum Hall States
Ganpathy Murthy, K. Park, R. Shankar +1
The microscopic approach of Murthy and Shankar, which has recently been used to calculate the transport gaps of quantum Hall states with fractions p/(2ps+1), also implies scaling r…
Field Theory of the Fractional Quantum Hall Effect-I
Ganpathy Murthy, R. Shankar
We provide details of a shorter letter and cond-mat/9702098 and some new results. We describe a Chern-Simons theory for the fractional quantum Hall states in which magnetoplasmon d…
Spin Polarizations at and about the Lowest Filled Landau Level
Tapash Chakraborty, P. Pietiläinen, R. Shankar
The spin polarization versus temperature at or near a fully filled lowest Landau level is explored for finite-size systems in a periodic rectangular geometry. Our results at …
Shape Deformation driven Structural Transitions in Quantum Hall Skyrmions
Madan Rao, Surajit Sengupta, R. Shankar
The Quantum Hall ground state away from can be described by a collection of interacting skyrmions. We show within the context of a nonlinear sigma model, that the classical…
Plasmons, Magnetoplasmons and the ν= 1/2 Quantum Hall Effect
R. Shankar, G. Murthy
We address the problem of separating the short-distance, high-energy physics of cyclotron motion from the long- distance, low-energy physics within the Lowest Landau Level in field…