Continuous-time quantum Monte Carlo study of local non-Fermi liquid state in the multichannel Anderson model

The impurity Green's function G_f in the local non-Fermi liquid state is evaluated by means of the continuous-time quantum Monte Carlo method extended to the multichannel Anderson model. For N = M (where N and M are numbers of spin components and channels, respectively), G_f is expressed as-ImG_f (ω + i0) = c - b|ω|^1/2, and the zero-frequency value c depends only on N (= M). A corresponding impurity self-energy at low frequencies is composed of two parts: a resonance term related to c, and a non-Fermi liquid term proportional to |ω| ^1/2. The characteristic energy scale is discussed in terms of the non-Fermi liquid term in the self-energy.