The variety of noise sources typical of the solid state represents the main limitation toward the realization of controllable and reliable quantum nanocircuits, as those allowing quantum computation. Such ``structured environments{''} are characterized by a non-monotonous noise spectrum sometimes showing resonances at selected frequencies. Here we focus on a prototype structured environment model: a two-state impurity linearly coupled to a dissipative harmonic bath. We identify the time scale separating Gaussian and non-Gaussian dynamical regimes of the Spin-Boson impurity. By using a path-integral approach we show that a qubit interacting with such a structured bath may probe the variety of environmental dynamical regimes.
Structured environments in solid state systems: crossover from Gaussian to non-Gaussian behavior
PALADINO, ELISABETTA;FALCI, Giuseppe;
2007-01-01
Abstract
The variety of noise sources typical of the solid state represents the main limitation toward the realization of controllable and reliable quantum nanocircuits, as those allowing quantum computation. Such ``structured environments{''} are characterized by a non-monotonous noise spectrum sometimes showing resonances at selected frequencies. Here we focus on a prototype structured environment model: a two-state impurity linearly coupled to a dissipative harmonic bath. We identify the time scale separating Gaussian and non-Gaussian dynamical regimes of the Spin-Boson impurity. By using a path-integral approach we show that a qubit interacting with such a structured bath may probe the variety of environmental dynamical regimes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.