Optical frequency synthesis and measurement using fibre-based femtosecond lasers

Abstract

We report the synthesis and measurement of an ultra-precise and extremely stable optical frequency in the telecommunications window around 1543 nm. Using a fibre-based femtosecond frequency comb we have phase-stabilised a fibre laser at 194 THz to an optical frequency standard at 344 THz, thus transferring the properties of the optical frequency standard to another spectral region. Relative to the optical frequency standard, the synthesised frequency at 194 THz is determined to within 1 mHz and its fractional frequency instability is measured to be less than 2*10^{-15} at 1 s, reaching 5*10^{-18} after 8000 s. We also measured the synthesised frequency against a caesium fountain clock: here the frequency comparison itself contributes less than 4 mHz (2*10^{-17}) to the uncertainty. Our results confirm the suitability of fibre based frequency comb technology for precision measurements and frequency synthesis, and enable long-distance comparison of optical clocks by using optical fibres to transmit the frequency information.

References in corpus (4)

• Observation of the 1S0 - 3P0 clock transition in 27Al+
• Ultra-precise measurement of optical frequency ratios
• Laser frequency stabilization to a single ion
• Laboratory Limits on Temporal Variations of Fundamental Constants: An Update

Cited by in corpus (10)

• Atomic Clocks for Geodesy
• Optical frequency transfer via 146 km fiber link with 10^{-19} relative accuracy
• Brillouin amplification in phase coherent transfer of optical frequencies over 480 km fiber
• Phase- coherent comparison of two optical frequency standards over 146 km using a telecommunication fiber link
• In-line extraction of an ultra-stable frequency signal over an optical fiber link
• Providing 1E-16 short-term stability of a 1.5 μm laser to optical clocks
• Long-distance remote comparison of ultrastable optical frequencies with 1e-15 instability in fractions of a second
• Interrogation laser for a strontium lattice clock
• A hybrid solution for simultaneous transfer of ultrastable optical frequency, RF frequency and UTC time-tags over optical fiber
• The stability of an optical clock laser transferred to the interrogation oscillator for a Cs fountain