Active sub-Rayleigh alignment of parallel or antiparallel laser beams

Abstract

We measure and stabilize the relative angle of (anti-)parallel laser beams to 5 nanoradian per root Hertz resolution by comparing the phases of radio frequency beat notes on a quadrant photodetector. The absolute accuracy is 5.1 microradian and 2.1 microradian for antiparallel and parallel beams, respectively, which is more than 6 and 16 times below the Rayleigh criterion.

References added; to appear in Optics Letters. 3 pages, 4 figures

References in corpus (1)

• Modern Michelson-Morley experiment using cryogenic optical resonators

Cited by in corpus (4)

• Overcoming the Rayleigh Criterion Limit with Optical Vortices
• Atom Interferometry with up to 24-Photon-Momentum-Transfer Beam Splitters
• A new photon recoil experiment: towards a determination of the fine structure constant
• Common mode noise rejection properties of amplitude and phase noise in a heterodyne interferometer