Dephasing by extremely dilute magnetic impurities revealed by Aharonov-Bohm oscillations.
نویسندگان
چکیده
We have probed the magnetic field dependence of the electron phase coherence time tau(phi) by measuring the Aharonov-Bohm conductance oscillations of mesoscopic Cu rings. Whereas tau(phi) determined from the low-field magnetoresistance saturates below 1 K, the amplitude of Aharonov-Bohm h/e oscillations increases strongly on a magnetic field scale proportional to the temperature. This provides strong evidence that a likely explanation for the frequently observed saturation of tau(phi) at low temperature in weakly disordered metallic thin films is the presence of extremely dilute magnetic impurities.
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عنوان ژورنال:
- Physical review letters
دوره 89 20 شماره
صفحات -
تاریخ انتشار 2002