RF frequency transfer over an urban 86 km fibre has been demonstrated with a resolution of 2×10 -18 at one day measuring time using an optical compensator. This result is obtained with a reference carrier frequency of 1 GHz, and a rapid scrambling of the polarisation state of the input light in order to reduce the sensitivity to the polarisation mode dispersion in the fibre. The limitation due to the fibre chromatic dispersion associated with the laser frequency fluctuations is highlighted and analyzed. A preliminary test of an extended compensated link over 186 km using optical amplifiers gives a resolution below 10 -17 at 1 day.

We present in this article results on a new dissemination system of an ultrastable reference signal at 100 MHz on a standard fiber network. The 100 MHz signal is simply transferred by amplitude modulation of an optical carrier. Two different approaches for compensating the noise introduced by the link have been implemented. The limits of the two systems are analyzed and several solutions are suggested in order to improve the frequency stability and to further extend the distribution distance. Nevertheless, our system is a good tool for the best cold atom fountains comparison between laboratories, up to 100 km, with a relative frequency resolution of 10 −14 at 1 s integration time and 10 −17 for 1 day of measurement. The distribution system may be upgraded to fulfill the stringent distribution requirements for the future optical clocks.

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We use a new technique to disseminate microwave reference signals along ordinary optical fiber. The fractional frequency resolution of a link of 86 km in length is 10(-17) for a one day integration time, a resolution higher than the stability of the best microwave or optical clocks. We use the link to compare the microwave reference and a CO2/OsO4 frequency standard that stabilizes a femtosecond laser frequency comb. This demonstrates a resolution of 3 x 10(-14) at 1 s. An upper value of the instability introduced by the femtosecond laser-based synthesizer is estimated as 1 x 10(-14) at 1 s.

In this article, we describe a new frequency synthesis system that includes a low phase noise cryogenic sapphire oscillator (CSO) and an H-maser to provide metrological low-noise signals to time and frequency experiments. Implementing this system as a local oscillator for a Cs cold atom fountain, a record frequency stability of 1.6×10−14τ−1∕2 is obtained.

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In this contribution, a first prototype for mobile respiratory motion detection using optical fibers embedded into textiles is presented. The developed system consists of a T-shirt with an integrated fiber sensor and a portable monitoring unit with a wireless communication link enabling the data analysis and visualization on a PC. A great effort is done worldwide to develop mobile solutions for health monitoring of vital signs for patients needing continuous medical care. Wearable, comfortable and smart textiles incorporating sensors are good approaches to solve this problem. In most of the cases, electrical sensors are integrated, showing significant limits such as for the monitoring of anaesthetized patients during Magnetic Resonance Imaging (MRI). OFSETH (Optical Fibre Embedded into technical Textile for Healthcare) uses optical sensor technologies to extend the current capabilities of medical technical textiles.

We report a PM all-normal, all-in-fiber passively mode-locked laser operating at 1030 nm. The main pulse shaping mechanism is provided by a tilted chirped-FBG. The laser delivers nanojoule range highly chirped pulses at a repetition rate of about 40 MHz. The FWHM of the optical spectrum is up to 7.8 nm leading to sub-500 fs compressed optical pulses. The influence of the filtering bandwidth and the output coupling ratio has been investigated.