Majorana path integral for nonequilibrium dynamics of two-level systems

Understand

We present a new field-theoretic approach to anaylize non-equilirbium dynamics of two-level systems (TLS), which is based on a correspondence between a driven TLS and a Majorana fermion field theory coupled to bosonic fields.

• This approach allows us to calculate analytically properties of non-linear TLS dynamics with an arbitrary accuracy.
• We apply our method to analyze specific TLS dynamics under a monochromatic periodic drive that is relevant to the problem of decoherence in Josephson junction qubits.
• It is demonstrated that the method gives the precise positions of the resonance peaks in the non-linear dielectric response function that are in agreement with numerical simulations.