Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 40: Poster Session Correlated Electrons
TT 40.9: Poster
Wednesday, March 13, 2013, 15:00–19:00, Poster D
Spin-boson coupling in continuous-time quantum Monte Carlo — •Junya Otsuki — Theoretische Physik III, Zentrum für Elektronische Korrelationen und Magnetismus, Universität Augsburg — Department of Physics, Tohoku University, Sendai, Japan
A vector bosonic field coupled to the electronic spin is treated by means of the continuous-time quantum Monte Carlo method.
In the Bose Kondo model with a sub-Ohmic density of states
ρB(ω) ∼ ω−s,
two contributions to the spin susceptibility, the Curie term T−1 and a bosonic fluctuating term T−s, are observed separately.
By including the fermionic bath,
a quantum phase transition is identified between the Kondo screened state and the bosonic fluctuating state, at which the effective moment and the local Fermi-liquid energy scale vanish.
It is demonstrated that the energy scale of the bosonic fluctuation is not affected by the existence of the quantum phase transition.
[1] J. Otsuki, arXiv:1211.5935.