title: Observation of "partial coherence" in an Aharonov-Bohm interferometer with a quantum dot.
abstract: We report experiments on the interference through spin states of electrons in a quantum dot (QD) embedded in an Aharonov-Bohm (AB) interferometer. We have picked up a spin-pair state, for which the environmental conditions are ideally similar. The AB amplitude is traced in a range of gate voltage that covers the pair. The behavior of the asymmetry in the amplitude around the two Coulomb peaks agrees with the theoretical prediction that the spin-flip process in a QD is related to the quantum dephasing of electrons. These results constitute evidence of "partial coherence" due to an entanglement of spins in the QD and in the interferometer.
authors.affiliation: Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Chiba 277-8581, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Aikawa
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Akira
authors.initials: A
authors.lastname: Sano
authors.forename: Shingo
authors.initials: S
authors.lastname: Katsumoto
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Iye