Observation of Zeeman splitting in universal conductance fluctuations.
نویسندگان
چکیده
We provide experimental evidence for a transition from a random-matrix ensemble with broken timereversal symmetry to an ensemble with partially broken spin-rotation symmetry. The transition from a Gaussian unitary ensemble to the ensemble in which the Zeeman degeneracy of electrons is lifted is accompanied by a factor of 2 change in 1/f noise fluctuations measured in a mesoscopic Li wire at low temperature. The magnetic-field scale characterizing the Zeeman crossover is determined by kBT , rather than by the Thouless energy.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 53 8 شماره
صفحات -
تاریخ انتشار 1996