[Seminar] Trapping Visons in Kitaev’s spin liquid by Professor. Masafumi Udagawa

Title:  Trapping Visons in Kitaev’s spin liquid

Speaker: Professor Masafumi Udagawa

Institution: Gakushuin University

Abstract:

Quantum spin liquid is a "Schrodinger's ice".

Macroscopic numbers of classical states make a coherent superposition to produce an quantum entangled state.

Recently, Kitaev’s model is drawing considerable attention as one of the promising systems to realize this unusual state in realistic materials.

In this system, spins are fractionalized into Majorana fermions and Visons, and the latter behave as abelian/non-abelian anyons. 

The understanding of these elementary excitations is essential to diagnose the Kitaev’s spin liquid phase in actual materials.

In this talk, we present an analytical solution of dynamical correlation function in this system.

With this solution, we will address how local disturbance of the system, such as impurity, manifests itself in the thermodynamic 

and dynamical properties, and associate them with the nature of fractionalized excitations. 

In particular, we will focus on the Vison zero-energy state appearing around the diluted site, and discuss how to observe it experimentally. 

Biography:

Ph. D in the scientific department of Tokyo University in 2007.

Working as a research associate from 2006 to 2015 in the applied physics department of Tokyo University 

Visiting researcher at Max Planck institute in Dresden (MPI PKS) in 2011

Start to work in a current place from 2015, as an associate professor in Gakushuin University