Title: Heat transfer from topologically protected dynamics of Majorana zero modes

Speaker: Dr. Alessandro Romito (Lancaster University)

Abstract:Quantum systems can have degenerate ground states protected against local fluctuations with exponential accuracy in the system size due to topology (as opposed to symmetry) properties. In certain systems, like topological superconductors, the degenerate ground state is spanned by zero energy modes with non-abelian statistics, Majorana zero-modes. These excitations are of extreme interest for both their fundamental properties and as a platform to implement protected unitary operations for quantum information processing. A number of experiments have reported signatures of Majorana zero modes in engineered superconducting nanostructures. The actual focus of research is on controlling and detecting their topological dynamics.

In this talk, after reviewing the general properties of Majorana zero modes, I will discuss the energetics associated with the topological protected dynamics, specifically a Majorana zero-modes braiding in 1-dimensional networks (e.g. quantum wires). This is a topologically protected non-trivial operation. I will show that the braiding operation is able to pump energy (heat) between two external reservoirs, as opposed to a vanishing pumped charge. The differential pumped heat per energy is quantised to a universal coefficient that reflects the system protected dynamics. I will finally discuss the robustness and generality of the findings and their implications for certain thermodynamic fluctuation theorems.

Time: Tuesday, March 19, 2019. 4:30 pm

Location: Lecture Room, 1st Floor, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4