Optical quantum nondemolition detection schemes in χ(2) media

Robert M. Shelby, M. D. Levenson, Stephen H. Perlmutter

M. D. Levenson, Robert M. Shelby, Stephen H. Perlmutter

Philippe Grangier

Ryotatsu Yanagimoto, Rajveer Nehra, Edwin Ng +2 more

We propose a scheme to realize a cubic quantum nondemolition (QND) Hamiltonian with optical parametric interactions. We show that strongly squeezed fundamental and second-harmonic fields propagating in a χ (2) nonlinear medium effectively evolve under a cubic QND Hamiltonian. We highlight the versatility offered by such a Hamiltonian for engineering non-Gaussian quantum states, such as Schrödinger cat states and cubic phase states. We show that our scheme can be highly tolerant of overall detection inefficiency with an auxiliary high-gain phase-sensitive optical amplifier. Our proposal involves parametric interactions in a mesoscopic photon-number regime, significantly enhancing the effective nonlinear coupling from the native single-photon coupling rate while providing powerful means to fight photon propagation loss. Experimental numbers suggest that our scheme might be feasible in the near future, particularly with pulsed nonlinear nanophotonics.

Robert M. Shelby

The concept of quantum nondemolition (QND) measurement is outlined in the context of quantum optics. As a prototypal QND measurement scheme, the interaction of a light beam with a classical mechanical oscillator via radiation pressure is outlined. Results of QND experiments using cross‐phase modulation of two co‐propagating beams in single mode optical fibers are reviewed, and the prospects for improved schemes briefly discussed.

Gerard J Milburn, Daniel F. Walls