Creating multi-beam interference from two-beam interference with assistant of harmonics generation

TL;DR

This paper introduces a nonlinear optics-based multi-beam interference method using cascading and recycling harmonics generation, achieving high-order harmonics and sharp interference fringes for advanced optical metrology.

Contribution

It proposes and experimentally verifies a novel nonlinear optics-based MBI principle with cascading, recycling, and optical power amplification, enabling high-order harmonics and high-finesse interference fringes.

Findings

Achieved 16th harmonic through cascading and recycling processes.

Observed evolution of interference fringes from sinusoidal to Lorentz-like curves.

Demonstrated potential for unlimited cascading processes with optical power amplification.

Abstract

Linear optics-based multi-beam interference (MBI), like the Fabry-Perot interferometer, plays an important role in precision optical metrology applications such as laser stabilization in optical clocks, precision spectroscopy, and gravitational wave detection. Here, we propose and experimentally verify a nonlinear optics-based MBI principle with the assistance of cascading and recycling harmonics generation of two-beam interference. By cascading and recycling the harmonics processes, in combining with optical power amplification (OPA) to compensate for power losses arising from limited nonlinear conversion efficiency, a total 16th harmonic is achieved, and the observed interference fringes gradually evolve from a sinusoidal curve to a Lorentz-like curve. In principle, there is no limitation on the number of cascading and recycling nonlinear processes with the assistance of OPAs and sharp interference fringes, analogous to those in a high-finesse cavity, can be obtained. The nonlinear optics-based MBI mechanism revealed here will find promising applications in precision optical metrology.