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Mileti, Gaetano

Nom
Mileti, Gaetano
Affiliation principale
Site web
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Professeur titulaire
Email
gaetano.mileti@unine.ch
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https://libra.unine.ch/handle/123456789/479

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  • Publication
    Métadonnées seulement
    High performance vapour-cell frequency standards
    (: Journal of Physics: Conference Series 723, 2015-10-27)
    Gharavipour, Mohammadreza 
    ;
    Affolderbach, Christoph 
    ;
    Kang, Songbai 
    ;
    Bandi Nagabhushan, Thejesh 
    ;
    Gruet, Florian 
    ;
    Pellaton, Matthieu 
    ;
    Mileti, Gaetano 
    We report our investigations on a compact high-performance rubidium (Rb) vapour-cell clock based on microwave-optical double-resonance (DR). These studies are done in both DR continuous-wave (CW) and Ramsey schemes using the same Physics Package (PP), with the same Rb vapour cell and a magnetron-type cavity with only 45 cm3 external volume. In the CW-DR scheme, we demonstrate a DR signal with a contrast of 26% and a linewidth of 334 Hz; in Ramsey-DR mode Ramsey signals with higher contrast up to 35% and a linewidth of 160 Hz have been demonstrated. Short-term stabilities of 1.4×10^-13 τ^-1/2 and 2.4×10^-13 τ^-1/2 are measured for CW-DR and Ramsey-DR schemes, respectively. In the Ramsey-DR operation, thanks to the separation of light and microwave interactions in time, the light-shift effect has been suppressed which allows improving the long-term clock stability as compared to CW-DR operation. Implementations in miniature atomic clocks are considered.
  • Publication
    Métadonnées seulement
    Optical clocks in space
    (: Elsevier Science Bv, 2006)
    Schiller, S
    ;
    Gorlitz, A
    ;
    Nevsky, A
    ;
    Koelemeij, J C J
    ;
    Wicht, A
    ;
    Gill, P
    ;
    Klein, H A
    ;
    Margolis, H S
    ;
    Mileti, Gaetano 
    ;
    Sterr, U
    ;
    Riehle, F
    ;
    Peik, E
    ;
    Tamm, C
    ;
    Ertmer, W
    ;
    Rasel, E
    ;
    Klein, V
    ;
    Salomon, C
    ;
    Tino, G M
    ;
    Lemonde, P
    ;
    Holzwarth, R
    ;
    Hansch, T W
    The performance of optical clocks has strongly progressed in recent years, and accuracies and instabilities of 1 part in 10(18) are expected in the near future. The operation of optical clocks in space provides new scientific and technological opportunities. In particular, an earth-orbiting satellite containing an ensemble of optical clocks would allow a precision measurement of the gravitational redshift, navigation with improved precision, mapping of the earth's gravitational potential by relativistic geodesy, and comparisons between ground clocks.
  • Publication
    Accès libre
    Microfabricated chip-scale rubidium plasma light source for miniature atomic clocks
    (2012-11-9)
    Venkatraman, Vinu
    ;
    Pétremand, Yves
    ;
    Affolderbach, Christoph 
    ;
    Mileti, Gaetano 
    ;
    De Rooij, Nicolaas-F.
    ;
    Shea, Herbert
  • Publication
    Accès libre
    High-performance laser pumped rubidium frequency standard for satellite navigation
    (2011)
    Bandi, T.
    ;
    Affolderbach, Christoph 
    ;
    Calosso, C.E.
    ;
    Mileti, Gaetano 
    Presented is a double-resonance continuous-wave laser-pumped rubidium (Rb) atomic clock with a short-term stability of 4 × 10(-13) t(-1/2) for integration times 1 s ≤ t ≤ 1000 s, and a medium- to longterm stability reaching the 1 × 10(-14) level at 10(4) s. The clock uses an Rb vapour cell with increased diameter of 25 mm, accommodated inside a newly developed compact magnetron-type microwave cavity. This results in a bigger signal with reduced linewidth, and thus improved short-term stability from a clock with 1 dm(3) physics package volume only. The medium- to long-term clock stability is achieved by minimising the effects of light-shift and temperature coefficient on the atoms. Potential applications of the clock are discussed.
  • Publication
    Métadonnées seulement
    Long-Term Stability Analysis Towards < 10-14 Level for a Highly Compact POP Rb Cell Atomic Clock
    (2019-4-14)
    Almat, Nil 
    ;
    Gharavipour, Mohammadreza 
    ;
    Moreno, William 
    ;
    Affolderbach, Christoph 
    ;
    Mileti, Gaetano 
    Long-term frequency instabilities in vapor-cell clocks mainly arise from fluctuations of the experimental and environmental parameters that are converted to clock frequency fluctuations via various physical processes. Here, we discuss the frequency sensitivities and the resulting stability limitations at one day timescale for a rubidium vapor-cell clock based on a compact magnetron-type cavity operated in air (no vacuum environment). Under ambient laboratory conditions, the external atmospheric pressure fluctuations may dominantly limit the clock stability via the barometric effect. We establish a complete long-term instability budget for our clock operated under stable pressure conditions. Where possible, the fluctuations of experimental parameters are measured via the atomic response. The measured clock instability of < 2·E10.14 at one day is limited by the intensity light-shift effect, which could further be reduced by active stabilization of the laser intensity or stronger optical pumping. The analyses reported here show the way towards simple, compact, and low-power vapor-cell atomic clocks with excellent long-term stabilities. ≤ 10.14 at one day when operated in ambient laboratory conditions.
  • Publication
    Métadonnées seulement
    High-contrast dark resonance on the D2 - line of 87Rb in a vapor cell with different directions of the pump - probe waves
    (2005-3-5)
    Kazakov, G.
    ;
    Mazets, I.
    ;
    Rozhdestvensky, Yu.
    ;
    Mileti, Gaetano 
    ;
    Delporte, J.
    ;
    Matisov, B.
    We propose a novel method enabling to create a high-contrast dark resonance in the 87Rb vapor D2-line. The method is based on an optical pumping of atoms into the working states by a two-frequency, linearly-polarized laser radiation propagating perpendicularly to the probe field. This new scheme is compared to the traditional scheme involving the σ+-polarized probe beam only, and significant improvement of the dark resonance parameters is found. Qualitative considerations are confirmed by numerical calculations.
  • Publication
    Métadonnées seulement
    Pump-probe spectroscopy and velocimetry of cold atoms in a slow beam
    (2001)
    Di Domenico, Gianni 
    ;
    Mileti, Gaetano 
    ;
    Thomann, Pierre 
    In this paper we report on the first purely "pump-probe" nonlinear laser spectroscopy results in a slow atomic beam. We have observed Raman, Rayleigh, and recoil-induced resonances (RIR) in a continuous beam of slow and cold cesium atoms extracted from a two-dimensional (2D) magneto-optical-trap (MOT) with the moving molasses technique. The RIR enabled us to measure the velocity distribution. therefore the average speed (0.6-4 m/s) and temperature (50-500 muK) of the atomic beam. Compared to time of flight, this technique has the advantage of being local, more sensitive in the low-velocity regime (v
  • Publication
    Métadonnées seulement
    Tuneable, stabilised diode lasers for compact atomic frequency standards and precision wavelength references
    (2005)
    Affolderbach, Christoph 
    ;
    Mileti, Gaetano 
    We describe the ongoing activities in Observatoire Cantonal de Neuchatel in the fields of precision laser spectroscopy and metrology of Rb atomic vapours. The work is motivated by the potentials of highly stable and narrowband laser light Sources for a variety of technical and scientific applications. We describe the use of extended-cavity diode lasers for the realisation of such narrowband light sources and the basic schemes under Study for their stabilisation, with focus on Doppler and sub-Doppler laser spectroscopy. The resulting laser systems offer good frequency stabilities and can be effectively miniaturised. This makes them interesting for direct applications of these techniques, as well as the presently developed precision instruments: compact atomic frequency standards for ground and space applications (GALILEO satellite positioning system), secondary optical frequency standards, transportable extended cavity diode lasers as seeding lasers, and others. (c) 2004 Elsevier Ltd. All rights reserved.
  • Publication
    Métadonnées seulement
    A new method of dark resonance excitation on D2 line in 87Rb vapor
    (2005-7-3)
    Kazakov, G.
    ;
    Matisov, B.
    ;
    Delporte, J.
    ;
    Mileti, Gaetano 
    A new method based on optical pumping is proposed for increasing the parameters of dark resonance excitation on D2 line in 87Rb vapor. The pumping is provided by linearly polarized two-frequency laser radiation propagating in the direction perpendicular to the probing field directed along the cell with atomic rubidium vapor. This method significantly improves the dark resonance parameters as compared to the case of pumping by a circularly polarized field. Qualitative considerations are confirmed by the results of numerical calculations.
  • Publication
    Accès libre