Control-free control: manipulating a quantum system using only a limited set of measurements

Abstract

We present and discuss different protocols for preparing an arbitrary quantum state of a qubit using only a restricted set of measurements, with no unitary operations at all. We show that an arbitrary state can indeed be prepared, provided that the available measurements satisfy certain requirements. Our results shed light on the role that measurement-induced back-action plays in quantum feedback control and the extent to which this back-action can be exploited in quantum-control protocols.

6 pages (two-column), 4 figures

References in corpus (6)

• Control of quantum phenomena: Past, present, and future
• Quantum control by von Neumann measurements
• The information about the state of a qubit gained by a weakly coupled detector
• Weak and strong measurement of a qubit using a switching-based detector
• Efficient Generation of a Maximally Entangled State by Repeated On- and Off-Resonant Scattering of Ancilla Qubits
• Entanglement Generation by Qubit Scattering in Three Dimensions

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