Spin-fluctuation-induced dephasing in a mesoscopic ring

Kicheon Kang, Sam Young Cho, Kyoung Wan Park
2002 Physical Review B (Condensed Matter)  
We investigate the persistent current in a hybrid Aharonov-Bohm ring - quantum dot system coupled to a reservoir which provides spin fluctuations. It is shown that the spin exchange interaction between the quantum dot and the reservoir induces dephasing in the absence of direct charge transfer. We demonstrate an anomalous nature of this spin-fluctuation induced dephasing which tends to enhance the persistent current. We explain our result in terms of the separation of the spin from the charge
more » ... n from the charge degree of freedom. The nature of the spin fluctuation induced dephasing is analyzed in detail.
doi:10.1103/physrevb.66.075312 fatcat:qlkbuhcq2bgwxkbs55pspf7qca