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Geometric phases of scattering states in a ring geometry: adiabatic pumping in mesoscopic devices

Huan-Qiang Zhou·Urban Lundin·Sam Young Cho
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Abstract

Geometric phases of scattering states in a ring geometry are studied based on a variant of the adiabatic theorem. Three time scales, i.e., the adiabatic period, the system time and the dwell time, associated with adiabatic scattering in a ring geometry plays a crucial role in determining geometric phases, in contrast to only two time scales, i.e., the adiabatic period and the dwell time, in an open system. We derive a formula connecting the gauge invariant geometric phases acquired by time-reversed scattering states and the circulating (pumping) current. A numerical calculation shows that the effect of the geometric phases is observable in a nanoscale electronic device.

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Huan-Qiang Zhou, Urban Lundin, Sam Young Cho. 2005-02-18. Geometric phases of scattering states in a ring geometry: adiabatic pumping in mesoscopic devices. https://doi.org/10.1088/0953-8984%2F17%2F7%2F001

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