High-Efficiency Quantum Interrogation Measurements via the Quantum Zeno Effect

P. G. Kwiat; A. G. White; J. R. Mitchell; O. Nairz; G. Weihs; H. Weinfurter; A. Zeilinger

doi:10.1103/PhysRevLett.83.4725

High-Efficiency Quantum Interrogation Measurements via the Quantum Zeno Effect

P. G. Kwiat, A. G. White, J. R. Mitchell, O. Nairz, G. Weihs, H. Weinfurter, and A. Zeilinger

Phys. Rev. Lett. 83, 4725 – Published 6 December 1999

Abstract

The phenomenon of quantum interrogation allows one to optically detect the presence of an absorbing object, without the measuring light interacting with it. In an application of the quantum Zeno effect, the object inhibits the otherwise coherent evolution of the light, such that the probability that an interrogating photon is absorbed can in principle be arbitrarily small. We have implemented this technique, achieving efficiencies of up to $73 %$ , and consequently exceeding the $50 %$ theoretical maximum of the original “interaction-free” measurement proposal. We have also predicted and experimentally verified a previously unsuspected dependence on loss.

Received 16 June 1999

DOI:https://doi.org/10.1103/PhysRevLett.83.4725

Authors & Affiliations

P. G. Kwiat^1,*, A. G. White¹, J. R. Mitchell¹, O. Nairz^2,†, G. Weihs^2,‡, H. Weinfurter^2,§, and A. Zeilinger^2,∥

¹Physics Division, P-23, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
²Institute for Experimental Physics, University of Innsbruck, Innsbruck 6020, Austria

^*Electronic address: Kwiat@lanl.gov
^†Current address: Inst. for Experimental Phys., Univ. of Vienna, Wien 1090, Austria.
^‡Current address: Inst. for Experimental Phys., Univ. of Vienna, Wien 1090, Austria.
^§Current address: Sektion Physik, Ludwig-Maximilians-Universität, D-80799 München, Germany.
^∥Current address: Inst. for Experimental Phys., Univ. of Vienna, Wien 1090, Austria.