Probe-Configuration-Dependent Decoherence in an Aharonov–Bohm Ring

Abstract

We have measured transport through mesoscopic Aharonov-Bohm (AB) rings with\ntwo different four-terminal configurations. While the amplitude and the phase\nof the AB oscillations are well explained within the framework of the\nLandaur-B\\"uttiker formalism, it is found that the probe configuration strongly\naffects the coherence time of the electrons, i.e., the decoherence is much\nreduced in the configuration of so-called nonlocal resistance. This result\nshould provide an important clue in clarifying the mechanism of quantum\ndecoherence in solids.\n