laserfrekvenskammare

Laserfrekvenskammare are optical devices used to generate a comb-like spectrum of equally spaced laser frequencies. This "frequency comb" is analogous to a ruler for light, with precisely defined and known frequency markers. The core principle behind their operation involves nonlinear optical processes, typically within an optical fiber or a microresonator. A continuous-wave laser is injected into a nonlinear medium, leading to the generation of new optical frequencies through processes like self-phase modulation.

The resulting output is a spectrum consisting of a series of sharp peaks, each separated by a constant frequency interval. This interval, known as the repetition rate, is typically determined by the physical properties of the nonlinear medium, such as the cavity length of a microresonator or the dispersion properties of an optical fiber. The spacing between the teeth of the comb is extremely stable and precise.

Laserfrekvenskammare have revolutionized metrology and spectroscopy due to their remarkable accuracy and stability. They are employed in applications such as high-precision frequency measurements, optical atomic clocks, and the characterization of optical systems. Their ability to act as a broadband optical frequency reference allows for unprecedented measurements in fields ranging from fundamental physics to advanced sensing. The development of frequency combs has been recognized with a Nobel Prize in Physics.