Quantum limits in the measurement of very small displacements in optical images

Claude Fabre (1) , J. -B. Fouet (1) , Agnès Maître (1)

1 LKB (Jussieu) - Laboratoire Kastler Brossel

We consider the problem of the measurement of very small displacements in the transverse plane of an optical image with a split photodetector. We show that the standard quantum limit for such a measurement, which is equal to the diffraction limit divided by the square root of the number of photons used in the measurement, cannot be overcome by use of ordinary single-mode squeezed light. We give the form of possible multimode nonclassical states of light, enabling us to enhance by orders of magnitude the resolution of such a measurement beyond the standard quantum limit.

Mots clés: image; quantum optics; sensibility; displacement

Domaines: Optique [physics.optics]

Claude Fabre, J. -B. Fouet, Agnès Maître. Quantum limits in the measurement of very small displacements in optical images. Optics Letters, 2000, 25 (1), pp.76. ⟨hal-00346049⟩