Nonequilibrium dynamics of anisotropic large spins in the kondo regime: time-dependent numerical renormalization group analysis.
نویسندگان
چکیده
We investigate the time-dependent Kondo effect in a single-molecule magnet (SMM) strongly coupled to metallic electrodes. Describing the SMM by a Kondo model with large spin S>1/2, we analyze the underscreening of the local moment and the effect of anisotropy terms on the relaxation dynamics of the magnetization. Underscreening by single-channel Kondo processes leads to a logarithmically slow relaxation, while finite uniaxial anisotropy causes a saturation of the SMM's magnetization. Additional transverse anisotropy terms induce quantum spin tunneling and a pseudospin-1/2 Kondo effect sensitive to the spin parity.
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ورودعنوان ژورنال:
- Physical review letters
دوره 100 8 شماره
صفحات -
تاریخ انتشار 2008