Long-distance remote comparison of ultrastable optical frequencies with 10(-15) instability in fractions of a second.

We demonstrate a fully optical, long-distance remote comparison of independent ultrastable optical frequencies reaching a short term stability that is superior to any reported remote comparison of optical frequencies. We use two ultrastable lasers, which are separated by a geographical distance of more than 50 km, and compare them via a 73 km long phase-stabilized fiber in a commercial telecommunication network. The remote characterization spans more than one optical octave and reaches a fractional frequency instability between the independent ultrastable laser systems of 3 x 10 (-15) in 0.1 s. The achieved performance at 100 ms represents an improvement by one order of magnitude to any previously reported remote comparison of optical frequencies and enables future remote dissemination of the stability of 100 mHz linewidth lasers within seconds.

[1]  Christian Chardonnet,et al.  Long-distance frequency transfer over an urban fiber link using optical phase stabilization , 2008, 0807.1882.

[2]  Patrick Gill,et al.  Vibration insensitive optical cavity , 2007 .

[3]  H. Stoehr,et al.  Diode laser with 1 Hz linewidth. , 2006, Optics letters.

[4]  D. Wineland,et al.  Frequency Ratio of Al+ and Hg+ Single-Ion Optical Clocks; Metrology at the 17th Decimal Place , 2008, Science.

[5]  L S Ma,et al.  Delivering the same optical frequency at two places: accurate cancellation of phase noise introduced by an optical fiber or other time-varying path. , 1994, Optics letters.

[6]  H. Schnatz,et al.  Optical frequency synthesis and measurement using fibre-based femtosecond lasers , 2008 .

[7]  H. Inaba,et al.  Measuring the frequency of a Sr optical lattice clock using a 120 km coherent optical transfer. , 2008, Optics letters.

[8]  Christian Chardonnet,et al.  Absolute frequency measurement of a SF6 two-photon line by use of a femtosecond optical comb and sum-frequency generation. , 2005, Optics letters.

[9]  S. Dawkins,et al.  Considerations on the Measurement of the Stability of Oscillators with Frequency Counters , 2007, 2007 IEEE International Frequency Control Symposium Joint with the 21st European Frequency and Time Forum.

[10]  Jun Ye,et al.  Coherent optical phase transfer over a 32-km fiber with 1 s instability at 10{-17}. , 2007, Physical review letters.

[11]  J. Millo,et al.  Thermal-noise-limited optical cavity , 2008, 2008 Conference on Precision Electromagnetic Measurements Digest.

[12]  Gesine Grosche,et al.  The Stability of an Optical Clock Laser Transferred to the Interrogation Oscillator for a Cs Fountain , 2008, IEEE Transactions on Instrumentation and Measurement.

[13]  J.J. McFerran,et al.  Considerations on the measurement of the stability of oscillators with frequency counters , 2007, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[14]  Paul A. Williams,et al.  High-stability transfer of an optical frequency over long fiber-optic links , 2008 .

[15]  Gesine Grosche,et al.  Phase-coherent comparison of two optical frequency standards over 146 km using a telecommunication fiber link , 2009, 0906.3476.

[16]  Fritz Riehle,et al.  Vibration-insensitive reference cavity for an ultra-narrow-linewidth laser , 2006 .

[17]  Christian Chardonnet,et al.  High-resolution optical frequency dissemination on a telecommunications network with data traffic. , 2009, Optics letters.

[18]  Jun Ye,et al.  Delivery of high-stability optical and microwave frequency standards over an optical fiber network , 2003 .

[19]  A. Clairon,et al.  Transmission of an Optical Carrier Frequency over a Telecommunication Fiber Link , 2007, 2007 Conference on Lasers and Electro-Optics (CLEO).

[20]  R. Holzwarth,et al.  Optical frequency transfer via 920 km fiber link with 10−19 relative accuracy , 2012, 2012 Conference on Lasers and Electro-Optics (CLEO).

[21]  N. Newbury,et al.  Coherent transfer of an optical carrier over 251 km. , 2007, Optics letters.

[22]  Jun Ye,et al.  Sr Lattice Clock at 1 × 10–16 Fractional Uncertainty by Remote Optical Evaluation with a Ca Clock , 2008, Science.

[23]  Kenji Numata,et al.  Thermal-noise limit in the frequency stabilization of lasers with rigid cavities. , 2004, Physical review letters.

[24]  Jun Ye,et al.  Remote transfer of ultrastable frequency references via fiber networks. , 2007, The Review of scientific instruments.

[25]  P. Lemonde,et al.  Ultrastable lasers based on vibration insensitive cavities , 2009, 0901.4717.