Strongly pumped SU(1,1) interferometer: loss-tolerant sensing below the shot-noise limit

QUEST Center event
Yes
Speaker
Maria Chekhova, Max Planck Institute for the Science of Light, Erlangen, Germany
Date
08/04/2018 - 18:00 - 17:00Add to Calendar 2018-04-08 17:00:00 2018-04-08 18:00:00 Strongly pumped SU(1,1) interferometer: loss-tolerant sensing below the shot-noise limit A nonlinear SU(1,1) interferometer is a sequence of two coherently pumped high-gain parametric amplifiers, realized through parametric down-conversion or four-wave mixing. The radiation emitted by the first amplifier can be amplified or deamplified in the second one, depending on the phase shifts acquired on the way. This makes the interferometer extremely sensitive to phase shifts, its sensitivity reaching the Heisenberg limit in the lossless case. Losses certainly reduce the phase sensitivity; however, detection loss can be overcome by making the interferometer gain-unbalanced. As we have shown theoretically [1] and experimentally [2], phase sensitivity below the shot-noise level can be achieved even with very inefficient detection provided that the second amplifier is pumped sufficiently strong. In my talk I will consider different constructions of an SU(1,1) interferometer based on high-gain parametric down-conversion. In particular, by imaging one parametric amplifier on the other one, the interferometer is made not sensitive to the radial mode content. Such a construction can be applied to sensing of orbital angular momentum perturbations.   [1] M. Manceau et al., New Journal of Physics 19, 013014 (2017). [2] M. Manceau et al., Phys. Rev. Lett. 119, 223604 (2017). Reznik Building 209, room 210 Department of Physics physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Reznik Building 209, room 210
Abstract

A nonlinear SU(1,1) interferometer is a sequence of two coherently pumped high-gain parametric amplifiers, realized through parametric down-conversion or four-wave mixing. The radiation emitted by the first amplifier can be amplified or deamplified in the second one, depending on the phase shifts acquired on the way. This makes the interferometer extremely sensitive to phase shifts, its sensitivity reaching the Heisenberg limit in the lossless case.

Losses certainly reduce the phase sensitivity; however, detection loss can be overcome by making the interferometer gain-unbalanced. As we have shown theoretically [1] and experimentally [2], phase sensitivity below the shot-noise level can be achieved even with very inefficient detection provided that the second amplifier is pumped sufficiently strong.

In my talk I will consider different constructions of an SU(1,1) interferometer based on high-gain parametric down-conversion. In particular, by imaging one parametric amplifier on the other one, the interferometer is made not sensitive to the radial mode content. Such a construction can be applied to sensing of orbital angular momentum perturbations.  

[1] M. Manceau et al., New Journal of Physics 19, 013014 (2017).

[2] M. Manceau et al., Phys. Rev. Lett. 119, 223604 (2017).

Last Updated Date : 27/03/2018