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arXiv · 1508.00807

U(1) and SU(2) quantum dissipative systems: The Caldeira-Leggett vs. the Amegaokar-Eckern-Schön approaches

Alexander Shnirman·Arijit Saha·Igor S. Burmistrov·Mikhail N. Kiselev·Alexander Altland·Yuval Gefen
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Abstract

There are two paradigmatic frameworks for treating quantum systems coupled to a dissipative environment: the Caldeira-Leggett and the Ambegaokar-Eckern-Schön approaches. Here we recall the differences between them, and explain the consequences when each is applied to a zero dimensional spin (possessing an SU(2) symmetry) in a dissipative environment (a dissipative quantum dot near or beyond the Stoner instability point).

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Alexander Shnirman, Arijit Saha, Igor S. Burmistrov, Mikhail N. Kiselev, Alexander Altland, Yuval Gefen. 2015-08-04. U(1) and SU(2) quantum dissipative systems: The Caldeira-Leggett vs. the Amegaokar-Eckern-Schön approaches. https://doi.org/10.1134/s1063776116030109

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