Charge Detection in a Closed-Loop Aharonov-Bohm Interferometer

Abstract

We report on a study of complementarity in a two-terminal "closed-loop" Aharonov-Bohm interferometer. In this interferometer, the simple picture of two-path interference cannot be applied. We introduce a nearby quantum point contact to detect the electron in a quantum dot inserted in the interferometer. We found that charge detection reduces but does not completely suppress the interference even in the limit of perfect detection. We attribute this phenomenon to the unique nature of the closed-loop interferometer. That is, the closed-loop interferometer cannot be simply regarded as a two-path interferometer because of multiple reflections of electrons. As a result, there exist indistinguishable paths of the electron in the interferometer and the interference survives even in the limit of perfect charge detection. This implies that charge detection is not equivalent to path detection in a closed-loop interferometer. We also discuss the phase rigidity of the transmission probability for a two-terminal conductor in the presence of a detector.

4 pages with 4 figures

References in corpus (13)

• Measurements with a noninvasive detector and dephasing mechanism
• Continuous weak measurement of quantum coherent oscillations
• Aharonov-Bohm oscillations in a mesoscopic ring with a quantum dot
• Dephasing and the Orthogonality Catastrophe in Tunneling through a Quantum Dot: the ``Which Path?'' Interferometer
• Dephasing in a quantum dot due to coupling with a quantum point contact
• Efficiency of Mesoscopic Detectors
• Charge Relaxation and Dephasing in Coulomb Coupled Conductors
• Measurement Process In a Two-Barrier System
• Controlled dephasing of a quantum dot in the Kondo regime
• Quantum Zeno effect and parametric resonance in mesoscopic physics
• Quantum dot dephasing by edge states
• Effects of Entanglement in Controlled Dephasing
• Decoherence of the Kondo Singlet via a Quantum Point Contact Detector

Cited by in corpus (12)

• Quantum mechanical complementarity probed in a closed-loop Aharonov-Bohm interferometer
• On the validity and breakdown of the Onsager symmetry in mesoscopic conductors interacting with environments
• Coulomb-interaction effects in full counting statistics of a quantum-dot Aharonov-Bohm interferometer
• An Electronic Mach-Zehnder Quantum Eraser
• Spin-dependent transport through quantum-dot Aharonov-Bohm interferometers
• Coulomb blockade double-dot Aharonov-Bohm interferometer: giant fluctuations
• Entanglement, measurement, and conditional evolution of the Kondo singlet interacting with a mesoscopic detector
• Phase and amplitude of Aharonov-Bohm oscillations in nonlinear three-terminal transport through a double quantum dot
• Coulomb blockade double-dot Aharonov-Bohm interferometer: harmonic decomposition of the interference pattern
• Dephasing of electrons in the Aharonov-Bohm interferometer with a single-molecular vibrational junction
• Phase rigidity breaking in open Aharonov-Bohm ring coupled to a cantilever
• Quantum-limited charge detection with two quantum point contacts