Richard Birrittella

Quantum-enhanced interferometry with weak thermal light

We propose and implement a procedure for enhancing the sensitivity with which one can determine the phase shift experienced by a thermal light beam possessing on average fewer than four photons in passing through an interferometer. Our procedure entails subtracting exactly one (which can be generalized to m) photon from the light field exiting an interferometer containing a phase-shifting element in one of its arms. As a consequence of the process of photon subtraction, the mean photon number and signal-to-noise ratio (SNR) of the resulting light field are increased, leading to an enhancement of the SNR of the interferometric signal for that fraction of the incoming data that leads to photon subtraction.Seyed Mohammad Hashemi Rafsanjani, ∗ Mohammad Mirhosseini, Omar S. Magaña-Loaiza, Bryan T. Gard, Richard Birrittella, B. E. Koltenbah, C. G. Parazzoli, Barbara A. Capron, Christopher C. Gerry, Jonathan P. Dowling, and Robert W. Boyd 5 Institute of Optics, University of Rochester, Rochester, New York 14627 Hearne Institute for Theoretical Physics and Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 Department of Physics and Astronomy, Lehman College, The City University of New York, Bronx, New York 10468 Boeing Research & Technology, Seattle, WA 98124 Department of Physics, University of Ottawa, Ottawa, ON, K1N6N5, Canada (Dated: May 19, 2016)

Photon Addition and Subtraction: New Strategies in Metrology

We propose a strategy that provides resolution and sensitivity below the standard metrology limits using photon addition/subtraction at the output.

Publisher's Note: State-projective scheme for generating pair coherent states in traveling-wave optical fields [Phys. Rev. A 84, 023810 (2011)]

This paper was published online on 9 August 2011 with a duplication of Fig. 4 in place of Fig. 1. Figure 1 has been correctly replaced as of 22 August 2011. Figure 1 is correct in the printed version of the journal.

Photon statistics, parity measurements, and Heisenberg-limited interferometry: example of the two-mode SU(1,1) SU(1,1) coherent states

Parity measurement-based quantum optical interferometry and metrology is known to be sensitive to the joint photon number distribution, , of the two-mode quantum states inside the interferometer. In cases where the statistics display a clustering of the populations around the borders (i.e. along the axes ) with a plateau over most of the interior, Heisenberg-limited (or super-sensitive) measurements of phase shifts are enabled. This follows from the heuristic number-phase uncertainty relation because of the uncertainty in the location of the photons being ΔN ∼  . As an example of the connection between the photon statistics and Heisenberg-limited phase uncertainty, we study parity measurement-based interferometry of the two-mode Barut–Girardello coherent states for SU(1,1) SU(1,1) obtained from the coupling together of two representations of SU(1,1) each associated with single-mode boson realizations with Bargmann indices as discussed by Gerry and Benmoussa [Phys. Rev. A 2000, 62, 033812]. These states generally have distributions with clustered populations along the borders. We demonstrate that these states do, indeed, lead to super-sensitive measurements and also lead to super-resolved interference fringes.