gesine grosche - Academia.edu (original) (raw)

Papers by gesine grosche

HAL (Le Centre pour la Communication Scientifique Directe), 2016

International Quantum Electronics Conference, Jun 17, 2007

The transmission of frequency information via fiber optic telecommunication networks offers an at... more The transmission of frequency information via fiber optic telecommunication networks offers an attractive option for a long distance frequency comparison and future public dissemination of ultra-precise frequencies. Here, mode locked erbium-doped fiber lasers that combine the field of frequency metrology with that of optical telecommunication, enable a new and attractive opportunity for a direct frequency comparison of distant optical clocks

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2010

We have explored the performance of 2 &am... more We have explored the performance of 2 "dark fibers" of a commercial telecommunication fiber link for a remote comparison of optical clocks. These fibers establish a network in Germany that will eventually link optical frequency standards at PTB with those at the Institute of Quantum Optics (IQ) at the Leibniz University of Hanover, and the Max Planck Institutes in Erlangen (MPL) and Garching (MPQ). We demonstrate for the first time that within several minutes a phase coherent comparison of clock lasers at the few 10(-15) level can also be accomplished when the lasers are more than 100 km apart. Based on the performance of the fiber link to the IQ, we estimate the expected stability for the link from PTB to MPQ via MPL that bridges a distance of approximately 900 km.

HAL (Le Centre pour la Communication Scientifique Directe), Apr 10, 2018

Laser Technik Journal, 2005

Die Verwendung von Lichtpulsen hat viele Vorteile Die Schnelligkeit von elektronischen Bauelement... more Die Verwendung von Lichtpulsen hat viele Vorteile Die Schnelligkeit von elektronischen Bauelementen wird kontinuierlich gesteigert. Rechnerprozessoren arbeiten bereits mit GHz-Taktraten, in der optischen Kommunikation werden bereits THz-Bitraten ins Auge gefasst. Kurz: Die Tatsache, dass auch Licht ganz normale elektromagnetische Strahlung-wie Hochfrequenz oder Mikrowellen-ist, wird technisch zunehmend genutzt.

2013 Joint European Frequency and Time Forum & International Frequency Control Symposium (EFTF/IFC), 2013

ABSTRACT We describe experiments with the AGH-designed fiber optic system for time and frequency ... more ABSTRACT We describe experiments with the AGH-designed fiber optic system for time and frequency dissemination, based on an active stabilization of the fiber delay. The measurements were performed at the Physikalisch-Technische Bundesanstalt, Braunschweig, over a field-deployed optical fiber loop going from PTB to the Magnesium clock laboratory in the Leibniz Universität Hannover and back (149 km, 45 dB attenuation).

Optics Express, 2014

In long-haul optical continuous-wave frequency transfer via fiber, remote bidirectional Er +-dope... more In long-haul optical continuous-wave frequency transfer via fiber, remote bidirectional Er +-doped fiber amplifiers are commonly used to mitigate signal attenuation. We demonstrate for the first time the ultrastable transfer of an optical frequency using a remote fiber Brillouin amplifier, placed in a server room along the link. Using it as the only means of remote amplification, on a 660 km loop of installed underground fiber we bridge distances of 250 km and 160 km between amplifications. Over several days of uninterrupted measurement we find an instability of the frequency transfer (Allan deviation of Λ-weighted data with 1 s gate time) of around 1 × 10 −19 and less for averaging times longer than 3000 s. The modified Allan deviation reaches 3 × 10 −19 at an averaging time of 100 s, corresponding to the current noise floor at this averaging time. For averaging times longer than 1000 s the modified Allan deviation is in the 10 −20 range. A conservative value of the overall accuracy is 1 × 10 −19 .

2012 European Frequency and Time Forum, 2012

ABSTRACT We describe a system that combines a cavity-stabilized laser, a hydrogen maser and a ces... more ABSTRACT We describe a system that combines a cavity-stabilized laser, a hydrogen maser and a cesium fountain clock. It provides an optical reference frequency that over the course of half a day drifts with less than 100 μHz/s. Furthermore it allows for a convenient measurement of an absolute frequency in the optical domain.

CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference, 2009

ABSTRACT This paper reports on an absolute frequency measurement on the 1S0rarr3P1 clock transiti... more ABSTRACT This paper reports on an absolute frequency measurement on the 1S0rarr3P1 clock transition of 24Mg at 457 nm based on cold atoms. The characterization of the short and long term stability of the system via telecom fiber network is presented. Measurement results reveal an improved data set, which is taken on a beam of thermal Mg atoms, by an order of magnitude in terms of accuracy.

A novel LDA technique which uses two single frequency lasers, one for each LDA beam is presented.... more A novel LDA technique which uses two single frequency lasers, one for each LDA beam is presented. In contrast to previously presented techniques using the optical frequency difference of the lasers for directional discrimination, the technique described here generates a quadrature signal pair by an optical superposition technique without any broad band electronical heterodyning. In order to extract the Doppler frequency optically, undesired mixing products have to be avoided. The realisation of this concept is based on the superposition of four light waves on one photodetector, where only two pairs of light waves are able to interfere forced by polarisation or by optical adjustment. Thus the photodector acts as an optoelectronical element to superimpose two optical beat signals, so that the envelope of the resulting output signal directly delivers the Doppler frequency (see figure 1(a)). 0 10-6 2.10-6 3.10-6 4.10-6 5.10-6 s time

We demonstrate a fully optical, long-distance remote comparison of independent ultrastable optica... more 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 × 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.

2014 IEEE International Frequency Control Symposium (FCS), 2014

A global positioning system (GPS) carrier-phase frequency transfer link along a baseline of 450 k... more A global positioning system (GPS) carrier-phase frequency transfer link along a baseline of 450 km has been established and is characterized by comparing it to a phase-stabilized optical fiber link of 920 km length, established between the two endpoints, the Max-Planck-Institut für Quantenoptik in Garching and the Physikalisch-Technische Bundesanstalt in Braunschweig. The characterization is accomplished by comparing two active hydrogen masers operated at both institutes. The masers serve as local oscillators and cancel out when the double differences are calculated, such that they do not constitute a limitation for the GPS link characterization. We achieve a frequency instability of 3 10 13 × − in 30 s and 5 10 16 × − for long averaging times. Frequency comparison results obtained via both links show no deviation larger than the statistical uncertainty of 6 10 16 × −. These results can also be interpreted as a successful cross-check of the measurement uncertainty of a truly remote end fiber link.

SPIE Proceedings, 2009

We have characterized the 24Mg optical frequency standard at the Institute of Quantum Optics (IQ)... more We have characterized the 24Mg optical frequency standard at the Institute of Quantum Optics (IQ), Hanover, using a clock laser at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, via a noise compensated 73 km fiber link and present preliminary results for the stability of the Mg standard. The stability of the clock laser (lambda = 657 nm) is transferred with a femtosecond

Physical Review Letters, 2013

To compare the increasing number of optical frequency standards, highly stable optical signals ha... more To compare the increasing number of optical frequency standards, highly stable optical signals have to be transferred over continental distances. We demonstrate optical-frequency transfer over a 1840-km underground optical fiber link using a single-span stabilization. The low inherent noise introduced by the fiber allows us to reach short term instabilities expressed as the modified Allan deviation of 2×10(-15) for a gate time τ of 1 s reaching 4×10(-19) in just 100 s. We find no systematic offset between the sent and transferred frequencies within the statistical uncertainty of about 3×10(-19). The spectral noise distribution of our fiber link at low Fourier frequencies leads to a τ(-2) slope in the modified Allan deviation, which is also derived theoretically.

Physical Review Letters, 2013

We have measured the frequency of the extremely narrow 1S-2S two-photon transition in atomic hydr... more We have measured the frequency of the extremely narrow 1S-2S two-photon transition in atomic hydrogen using a remote cesium fountain clock with the help of a 920 km stabilized optical fiber. With an improved detection method we obtain f 1S-2S ¼ 2466 061 413 187 018 ð11Þ Hz with a relative uncertainty of 4:5 Â 10 À15 , confirming our previous measurement obtained with a local cesium clock [C. G. Parthey et al., Phys. Rev. Lett. 107, 203001 (2011)]. Combining these results with older measurements, we constrain the linear combinations of Lorentz boost symmetry violation parameters c ðTXÞ ¼ ð3:1 AE 1:9Þ Â 10 À11 and 0:92c ðTYÞ þ 0:40c ðTZÞ ¼ ð2:6 AE 5:3Þ Â 10 À11 in the standard model extension framework [D.

Physical Review A, 2006

We report measurements of the transition frequencies 4sS1/22-4pP1/22 and 4sS1/22-4pP3/22 of the p... more We report measurements of the transition frequencies 4sS1/22-4pP1/22 and 4sS1/22-4pP3/22 of the potassium isotopes 39, 40, and 41 through an atomic beam experiment with a fractional uncertainty of about 2×10-10 . For frequency calibration, a fs-laser comb referenced to a Cs atomic clock was used. Compared to previous results, hyperfine constants for the states 4pP1/22 and 4pP3/22 and isotope shifts

Physical Review A, 2008

We report on a frequency measurement of the (3s 2) 1 S0 → (3s3p) 3 P1 clock transition of 24 Mg o... more We report on a frequency measurement of the (3s 2) 1 S0 → (3s3p) 3 P1 clock transition of 24 Mg on a thermal atomic beam. The intercombination transition has been referenced to a portable primary Cs frequency standard with the help of a femtosecond fiber laser frequency comb. The achieved uncertainty is 2.5 × 10 −12 which corresponds to an increase in accuracy of six orders of magnitude compared to previous results. The measured frequency value permits the calculation of several other optical transitions from 1 S0 to the 3 PJ-level system for 24 Mg, 25 Mg and 26 Mg. We describe in detail the components of our optical frequency standard like the stabilized spectroscopy laser, the atomic beam apparatus used for Ramsey-Bordé interferometry and the frequency comb generator and discuss the uncertainty contributions to our measurement including the first and second order Doppler effect. An upper limit of 3 × 10 −13 in one second for the short term instability of our optical frequency standard was determined by comparison with a GPS disciplined quartz oscillator.

HAL (Le Centre pour la Communication Scientifique Directe), 2016

International Quantum Electronics Conference, Jun 17, 2007

The transmission of frequency information via fiber optic telecommunication networks offers an at... more The transmission of frequency information via fiber optic telecommunication networks offers an attractive option for a long distance frequency comparison and future public dissemination of ultra-precise frequencies. Here, mode locked erbium-doped fiber lasers that combine the field of frequency metrology with that of optical telecommunication, enable a new and attractive opportunity for a direct frequency comparison of distant optical clocks

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2010

We have explored the performance of 2 &am... more We have explored the performance of 2 "dark fibers" of a commercial telecommunication fiber link for a remote comparison of optical clocks. These fibers establish a network in Germany that will eventually link optical frequency standards at PTB with those at the Institute of Quantum Optics (IQ) at the Leibniz University of Hanover, and the Max Planck Institutes in Erlangen (MPL) and Garching (MPQ). We demonstrate for the first time that within several minutes a phase coherent comparison of clock lasers at the few 10(-15) level can also be accomplished when the lasers are more than 100 km apart. Based on the performance of the fiber link to the IQ, we estimate the expected stability for the link from PTB to MPQ via MPL that bridges a distance of approximately 900 km.

HAL (Le Centre pour la Communication Scientifique Directe), Apr 10, 2018

Laser Technik Journal, 2005

Die Verwendung von Lichtpulsen hat viele Vorteile Die Schnelligkeit von elektronischen Bauelement... more Die Verwendung von Lichtpulsen hat viele Vorteile Die Schnelligkeit von elektronischen Bauelementen wird kontinuierlich gesteigert. Rechnerprozessoren arbeiten bereits mit GHz-Taktraten, in der optischen Kommunikation werden bereits THz-Bitraten ins Auge gefasst. Kurz: Die Tatsache, dass auch Licht ganz normale elektromagnetische Strahlung-wie Hochfrequenz oder Mikrowellen-ist, wird technisch zunehmend genutzt.

2013 Joint European Frequency and Time Forum & International Frequency Control Symposium (EFTF/IFC), 2013

ABSTRACT We describe experiments with the AGH-designed fiber optic system for time and frequency ... more ABSTRACT We describe experiments with the AGH-designed fiber optic system for time and frequency dissemination, based on an active stabilization of the fiber delay. The measurements were performed at the Physikalisch-Technische Bundesanstalt, Braunschweig, over a field-deployed optical fiber loop going from PTB to the Magnesium clock laboratory in the Leibniz Universität Hannover and back (149 km, 45 dB attenuation).

Optics Express, 2014

In long-haul optical continuous-wave frequency transfer via fiber, remote bidirectional Er +-dope... more In long-haul optical continuous-wave frequency transfer via fiber, remote bidirectional Er +-doped fiber amplifiers are commonly used to mitigate signal attenuation. We demonstrate for the first time the ultrastable transfer of an optical frequency using a remote fiber Brillouin amplifier, placed in a server room along the link. Using it as the only means of remote amplification, on a 660 km loop of installed underground fiber we bridge distances of 250 km and 160 km between amplifications. Over several days of uninterrupted measurement we find an instability of the frequency transfer (Allan deviation of Λ-weighted data with 1 s gate time) of around 1 × 10 −19 and less for averaging times longer than 3000 s. The modified Allan deviation reaches 3 × 10 −19 at an averaging time of 100 s, corresponding to the current noise floor at this averaging time. For averaging times longer than 1000 s the modified Allan deviation is in the 10 −20 range. A conservative value of the overall accuracy is 1 × 10 −19 .

2012 European Frequency and Time Forum, 2012

ABSTRACT We describe a system that combines a cavity-stabilized laser, a hydrogen maser and a ces... more ABSTRACT We describe a system that combines a cavity-stabilized laser, a hydrogen maser and a cesium fountain clock. It provides an optical reference frequency that over the course of half a day drifts with less than 100 μHz/s. Furthermore it allows for a convenient measurement of an absolute frequency in the optical domain.

CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference, 2009

ABSTRACT This paper reports on an absolute frequency measurement on the 1S0rarr3P1 clock transiti... more ABSTRACT This paper reports on an absolute frequency measurement on the 1S0rarr3P1 clock transition of 24Mg at 457 nm based on cold atoms. The characterization of the short and long term stability of the system via telecom fiber network is presented. Measurement results reveal an improved data set, which is taken on a beam of thermal Mg atoms, by an order of magnitude in terms of accuracy.

A novel LDA technique which uses two single frequency lasers, one for each LDA beam is presented.... more A novel LDA technique which uses two single frequency lasers, one for each LDA beam is presented. In contrast to previously presented techniques using the optical frequency difference of the lasers for directional discrimination, the technique described here generates a quadrature signal pair by an optical superposition technique without any broad band electronical heterodyning. In order to extract the Doppler frequency optically, undesired mixing products have to be avoided. The realisation of this concept is based on the superposition of four light waves on one photodetector, where only two pairs of light waves are able to interfere forced by polarisation or by optical adjustment. Thus the photodector acts as an optoelectronical element to superimpose two optical beat signals, so that the envelope of the resulting output signal directly delivers the Doppler frequency (see figure 1(a)). 0 10-6 2.10-6 3.10-6 4.10-6 5.10-6 s time

We demonstrate a fully optical, long-distance remote comparison of independent ultrastable optica... more 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 × 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.

2014 IEEE International Frequency Control Symposium (FCS), 2014

A global positioning system (GPS) carrier-phase frequency transfer link along a baseline of 450 k... more A global positioning system (GPS) carrier-phase frequency transfer link along a baseline of 450 km has been established and is characterized by comparing it to a phase-stabilized optical fiber link of 920 km length, established between the two endpoints, the Max-Planck-Institut für Quantenoptik in Garching and the Physikalisch-Technische Bundesanstalt in Braunschweig. The characterization is accomplished by comparing two active hydrogen masers operated at both institutes. The masers serve as local oscillators and cancel out when the double differences are calculated, such that they do not constitute a limitation for the GPS link characterization. We achieve a frequency instability of 3 10 13 × − in 30 s and 5 10 16 × − for long averaging times. Frequency comparison results obtained via both links show no deviation larger than the statistical uncertainty of 6 10 16 × −. These results can also be interpreted as a successful cross-check of the measurement uncertainty of a truly remote end fiber link.

SPIE Proceedings, 2009

We have characterized the 24Mg optical frequency standard at the Institute of Quantum Optics (IQ)... more We have characterized the 24Mg optical frequency standard at the Institute of Quantum Optics (IQ), Hanover, using a clock laser at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, via a noise compensated 73 km fiber link and present preliminary results for the stability of the Mg standard. The stability of the clock laser (lambda = 657 nm) is transferred with a femtosecond

Physical Review Letters, 2013

To compare the increasing number of optical frequency standards, highly stable optical signals ha... more To compare the increasing number of optical frequency standards, highly stable optical signals have to be transferred over continental distances. We demonstrate optical-frequency transfer over a 1840-km underground optical fiber link using a single-span stabilization. The low inherent noise introduced by the fiber allows us to reach short term instabilities expressed as the modified Allan deviation of 2×10(-15) for a gate time τ of 1 s reaching 4×10(-19) in just 100 s. We find no systematic offset between the sent and transferred frequencies within the statistical uncertainty of about 3×10(-19). The spectral noise distribution of our fiber link at low Fourier frequencies leads to a τ(-2) slope in the modified Allan deviation, which is also derived theoretically.

Physical Review Letters, 2013

We have measured the frequency of the extremely narrow 1S-2S two-photon transition in atomic hydr... more We have measured the frequency of the extremely narrow 1S-2S two-photon transition in atomic hydrogen using a remote cesium fountain clock with the help of a 920 km stabilized optical fiber. With an improved detection method we obtain f 1S-2S ¼ 2466 061 413 187 018 ð11Þ Hz with a relative uncertainty of 4:5 Â 10 À15 , confirming our previous measurement obtained with a local cesium clock [C. G. Parthey et al., Phys. Rev. Lett. 107, 203001 (2011)]. Combining these results with older measurements, we constrain the linear combinations of Lorentz boost symmetry violation parameters c ðTXÞ ¼ ð3:1 AE 1:9Þ Â 10 À11 and 0:92c ðTYÞ þ 0:40c ðTZÞ ¼ ð2:6 AE 5:3Þ Â 10 À11 in the standard model extension framework [D.

Physical Review A, 2006

We report measurements of the transition frequencies 4sS1/22-4pP1/22 and 4sS1/22-4pP3/22 of the p... more We report measurements of the transition frequencies 4sS1/22-4pP1/22 and 4sS1/22-4pP3/22 of the potassium isotopes 39, 40, and 41 through an atomic beam experiment with a fractional uncertainty of about 2×10-10 . For frequency calibration, a fs-laser comb referenced to a Cs atomic clock was used. Compared to previous results, hyperfine constants for the states 4pP1/22 and 4pP3/22 and isotope shifts

Physical Review A, 2008

We report on a frequency measurement of the (3s 2) 1 S0 → (3s3p) 3 P1 clock transition of 24 Mg o... more We report on a frequency measurement of the (3s 2) 1 S0 → (3s3p) 3 P1 clock transition of 24 Mg on a thermal atomic beam. The intercombination transition has been referenced to a portable primary Cs frequency standard with the help of a femtosecond fiber laser frequency comb. The achieved uncertainty is 2.5 × 10 −12 which corresponds to an increase in accuracy of six orders of magnitude compared to previous results. The measured frequency value permits the calculation of several other optical transitions from 1 S0 to the 3 PJ-level system for 24 Mg, 25 Mg and 26 Mg. We describe in detail the components of our optical frequency standard like the stabilized spectroscopy laser, the atomic beam apparatus used for Ramsey-Bordé interferometry and the frequency comb generator and discuss the uncertainty contributions to our measurement including the first and second order Doppler effect. An upper limit of 3 × 10 −13 in one second for the short term instability of our optical frequency standard was determined by comparison with a GPS disciplined quartz oscillator.