Quantum Berezinskii-Kosterltz-Thouless Transition for Topological Insulator : A Detail Study of Renormalization Group Theory

Ranjith Kumar R, S Rahul, Surya Narayan, Sujit Sarkar

Published Oct 2, 2018• 0 citations

Abstract

We present extensive calculation and the results of quantum Berezinskii-Kosterlitz-Thouless (BKT) transition for interacting helical liquid system. This system shows the quantum BKT transition for the different physical situation which we present by two model Hamiltonians. We derive the renormalization group (RG) equations explicitly and present the flow lines behavior. We also present RG flow lines based on the exact solution. We observe that the Majorana fermion zero modes physics and the gapped Ising phase of the system. We also observe that the evidence of gapless Luttinger liquid phase as a common phase for both quantum BKT transitions.

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