Phase estimation with nonunitary interferometers: Information as a metric

Journal Article · Sun May 15 00:00:00 EDT 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.83.053601· OSTI ID:21546814

Bahder, Thomas B ^[1]

---

1. Aviation and Missile Research, Development, and Engineering Center, U.S. Army RDECOM, Redstone Arsenal, Alabama 35898 (United States)

Determining the phase in one arm of a quantum interferometer is discussed taking into account the three nonideal aspects in real experiments: nondeterministic state preparation, nonunitary state evolution due to losses during state propagation, and imperfect state detection. A general expression is written for the probability of a measurement outcome taking into account these three nonideal aspects. As an example of applying the formalism, the classical Fisher information and fidelity (Shannon mutual information between phase and measurements) are computed for few-photon Fock and N00N states input into a lossy Mach-Zehnder interferometer. These three nonideal aspects lead to qualitative differences in phase estimation, such as a decrease in fidelity and Fisher information that depends on the true value of the phase.

• OSTI ID: 21546814
• Journal Information: Physical Review. A, Vol. 83, Issue 5; Other Information: DOI: 10.1103/PhysRevA.83.053601; (c) 2011 American Institute of Physics; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
DETECTION
HARTREE-FOCK METHOD
INFORMATION
MACH-ZEHNDER INTERFEROMETER
METRICS
PHASE STUDIES
PHOTONS
PROBABILITY
QUANTUM STATES
APPROXIMATIONS
BOSONS
CALCULATION METHODS
ELEMENTARY PARTICLES
INTERFEROMETERS
MASSLESS PARTICLES
MEASURING INSTRUMENTS