Dynamics of a large spin with weak dissipation q
نویسندگان
چکیده
We investigate the generalization of the spin-boson model to arbitrary spin size. The Born–Markov approximation is employed to derive a master equation in the regime of small coupling strengths to the environment. For spin one half, the master equation transforms into a set of Bloch equations, the solution of which is in good agreement with results of the spin-boson model for weak ohmic dissipation. For larger spins, we find a superradiance-like behavior known from the Dicke model. The influence of the nonresonant bosons of the dissipative environment can lead to the formation of a beat pattern in the dynamics of the z-component of the spin. The beat frequency is approximately proportional to the cutoff xc of the spectral function. 2003 Elsevier B.V. All rights reserved.
منابع مشابه
3 Dynamics of a large spin with weak dissipation ⋆
We investigate the generalization of the spin-boson model to arbitrary spin size. The Born-Markov approximation is employed to derive a master equation in the regime of small coupling strengths to the environment. For spin one half, the master equation transforms into a set of Bloch equations, the solution of which is in good agreement with results of the spin-boson model for weak ohmic dissipa...
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تاریخ انتشار 2003