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Weak Measurements: Typical Weak and Superweak Values


Affiliations
1 Department of Physics, Indian Institute of Technology, Kharagpur 721 302, India
 

Weak value is a physical property of a quantum system which manifests itself through a weak measurement using different pre- and post-selected ensembles of the system. The weak values of an operator may differ significantly from its eigenvalues and can even lie outside the spectrum if it is bound: they can be 'superweak'. The latter, originating due to a coherent superposition of waves, may appear as a 'supershift' on the measuring device. This property has potential application in the amplification and detection of extremely weak signals.

Keywords

Eigenvalue, Ensemble, Quantum System, Weak Measurement.
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  • Weak Measurements: Typical Weak and Superweak Values

Abstract Views: 371  |  PDF Views: 108

Authors

Pragya Shukla
Department of Physics, Indian Institute of Technology, Kharagpur 721 302, India

Abstract


Weak value is a physical property of a quantum system which manifests itself through a weak measurement using different pre- and post-selected ensembles of the system. The weak values of an operator may differ significantly from its eigenvalues and can even lie outside the spectrum if it is bound: they can be 'superweak'. The latter, originating due to a coherent superposition of waves, may appear as a 'supershift' on the measuring device. This property has potential application in the amplification and detection of extremely weak signals.

Keywords


Eigenvalue, Ensemble, Quantum System, Weak Measurement.

References





DOI: https://doi.org/10.18520/cs%2Fv109%2Fi11%2F2039-2043