Null weak values in multi-level systems

Abstract

A two-step measurement protocol of a quantum system, known as weak value (WV), has been introduced more than two decades ago by Aharonov et al. [1], and has since been studied in various contexts. Here we discuss another two-step measurement protocol which we dub null weak value (NWV). The protocol consists of a partial-collapse measurement followed by quantum manipulation on the system and finally a strong measurement. The first step is a strong measurement which takes place with small probability. The second strong measurement is used as postselection on the outcome of the earlier step. Not being measured in the partial-collapse stage (null outcome) leads to a non-trivial correlation between the two measurements. The NVW protocol, first defined for a two-level system [2], is generalized to a multi-level system, and compared to the standard-WV protocol.

5 pages, 2 figures, conference proceeding

References in corpus (15)

• Ultrasensitive Beam Deflection Measurement via Interferometric Weak Value Amplification
• Measuring small longitudinal phase shifts: weak measurements or standard interferometry?
• Quantum weak values
• Complex weak values in quantum measurement
• Weak values and the Leggett-Garg inequality in solid-state qubits
• Uncollapsing of a quantum state in a superconducting phase qubit
• Optimizing the Signal to Noise Ratio of a Beam Deflection Measurement with Interferometric Weak Values
• Weak Values, Quantum Trajectories, and the Stony-Brook Cavity QED experiment
• Continuous phase amplification with a Sagnac interferometer
• Contextual Values of Observables in Quantum Measurements
• Quantum measurements with preselection and postselection
• Charge sensing amplification via weak values measurement
• Weak values of electron spin in a double quantum dot
• Tomography of many-body weak values: Mach-Zehnder interferometry
• Coherence of a Josephson phase qubit under partial-collapse measurement

Cited by in corpus (7)

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• Broadening the scope of weak quantum measurements I: A single particle accurately measured yet left superposed
• Null Values and Quantum State Discrimination
• Measuring cotunneling in its wake
• Disturbance in weak measurements and the difference between quantum and classical weak values
• Many-body manifestation of interaction-free measurement: the Elitzur-Vaidman bomb