Weak Measurement of Qubit Oscillations with Strong Response Detectors: Violation of the Fundamental Bound Imposed on Linear Detectors
arXiv:0806.2502 · doi:10.1103/PhysRevB.79.075320
Abstract
We investigate the continuous weak measurement of a solid-state qubit by single electron transistors in nonlinear response regime. It is found that the signal-to-noise ratio can violate the universal upper bound imposed quantum mechanically to any linear response detectors. We understand the violation by means of the cross-correlation of the detector currents.
4 pages, 4 figures
References in corpus (18)
- Quantum state engineering with Josephson-junction devices
- Counting statistics of single-electron transport in a quantum dot
- Selective quantum evolution of a qubit state due to continuous measurement
- Continuous weak measurement of quantum coherent oscillations
- Quantum-Limited Measurement and Information in Mesoscopic Detectors
- Efficiency of Mesoscopic Detectors
- Output spectrum of a detector measuring quantum oscillations
- Spontaneous Relaxation of a Charge Qubit under Electrical Measurement
- Counting statistics and detector properties of quantum point contacts
- Quantum limited sensitivity of SET-based displacement detectors
- Continuous quantum measurement with independent detector cross-correlations
- Calculation of the current noise spectrum in mesoscopic transport: an efficient quantum master equation approach
- Quantum Nondemolition Measurement of a Kicked Qubit
- Single qubit measurements with an asymmetric single-electron transistor
- Quantum nondemolition measurements of a qubit
- Sensitivity and back-action in charge qubit measurements by a strongly coupled single-electron transistor
- Quantum measurement characteristics of double-dot single electron transistor
- Continuous weak measurement and feedback control of a solid-state charge qubit: physical unravelling of non-Lindblad master equation