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Author

Louis Marmet

Other affiliations: University of Toronto
Bio: Louis Marmet is an academic researcher from National Research Council. The author has contributed to research in topics: Laser & Atomic clock. The author has an hindex of 14, co-authored 56 publications receiving 1126 citations. Previous affiliations of Louis Marmet include University of Toronto.


Papers
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Journal ArticleDOI
TL;DR: It is shown that dc-electric-field coupling of the 2 {ital s} and 2{ital p} states in atomic hydrogen leads to resonantly enhanced second-order susceptibility with reduced absorption at the second-harmonic wavelength, and exact phase matching at the center of the Stark-split components.
Abstract: We show that dc-electric-field coupling of the 2s and 2p states in atomic hydrogen leads to resonantly enhanced second-order susceptibility with reduced absorption at the second-harmonic wavelength, and exact phase matching at the center of the Stark-split components.

243 citations

Journal ArticleDOI
TL;DR: A simple method for cancelling the electric quadrupole shift based on measurements of the Zeeman spectrum of the clock transition is presented, which is easy to implement and yields very high cancellation levels.
Abstract: The electric quadrupole shift is presently the most significant source of uncertainty on the systematic shifts for several single-ion optical frequency standards. We present a simple method for canceling this shift based on measurements of the Zeeman spectrum of the clock transition. This method is easy to implement and yields very high cancellation levels. A fractional uncertainty of $5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}18}$ for the canceled quadrupole shift is estimated for a measurement of the absolute frequency of the $5s\text{ }^{2}S_{1/2}--4d\text{ }^{2}D_{5/2}$ clock transition of $^{88}\mathrm{Sr}^{+}$.

131 citations

Journal ArticleDOI
TL;DR: In this paper, an optical frequency chain referenced to a Cs atomic clock has been used to measure directly the frequency of the electric quadrupole allowed $5s^{2}S{1/2}\ensuremath{-}4d^{2]D{5/2}$ transition at 445 THz in a single, trapped, and laser cooled ion.
Abstract: An optical frequency chain referenced to a Cs atomic clock has been used to measure directly the frequency of the electric quadrupole allowed $5s^{2}S_{1/2}\ensuremath{-}4d^{2}D_{5/2}$ transition at 445 THz in a single, trapped, and laser cooled ${}^{88}{\mathrm{Sr}}^{+}$ ion. A transition frequency, ${f}_{S\ensuremath{-}D}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}444779044095.4\mathrm{kHz}$ with an estimated standard uncertainty of 0.2 kHz has been determined. Intrinsic offsets of the probed ion transition in the current experiment are calculated to be at the ${10}^{\ensuremath{-}15}$ level.

117 citations

Journal ArticleDOI
TL;DR: In this article, a frequency lock was developed which stabilizes a portion of the output from an ultrastable diode laser to the narrow 5s 2 S 1/2 −4d 2 D 5/2 transition at 445 THz (674 nm) of a single, trapped and laser cooled 88Sr+ ion.

79 citations

Journal ArticleDOI
TL;DR: Using an iodine-stabilized He-Ne laser as a transfer oscillator, absolute measurements of the optical frequency from a traditional frequency synthesis chain based on harmonic generation and from the frequency division technique of an ultrawide bandwidth femtosecond frequency comb are compared.
Abstract: Using an iodine-stabilized He-Ne laser as a transfer oscillator, we compare absolute measurements of the optical frequency from a traditional frequency synthesis chain based on harmonic generation and from the frequency division technique of an ultrawide bandwidth femtosecond frequency comb. The agreement between these two measurements, both linked to the Cs standard, is 220+/-770 Hz, yielding a measurement accuracy of 1.6x10(-12). We report 473 612 353 604.8+/-1.2 kHz as a preliminary updated value of the absolute frequency of the " f" component for the He-Ne laser international standard at 633 nm.

76 citations


Cited by
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Journal ArticleDOI
TL;DR: Electromagnetic induced transparency is a technique for eliminating the effect of a medium on a propagating beam of electromagnetic radiation EIT may also be used, but under more limited conditions, to eliminate optical self-focusing and defocusing and to improve the transmission of laser beams through inhomogeneous refracting gases and metal vapors, as figure 1 illustrates.
Abstract: Electromagnetically induced transparency is a technique for eliminating the effect of a medium on a propagating beam of electromagnetic radiation EIT may also be used, but under more limited conditions, to eliminate optical self‐focusing and defocusing and to improve the transmission of laser beams through inhomogeneous refracting gases and metal vapors, as figure 1 illustrates The technique may be used to create large populations of coherently driven uniformly phased atoms, thereby making possible new types of optoelectronic devices

3,269 citations

Journal ArticleDOI
14 Mar 2002-Nature
TL;DR: The ability to count optical oscillations of more than 1015 cycles per second facilitates high-precision optical spectroscopy, and has led to the construction of an all-optical atomic clock that is expected eventually to outperform today's state-of-the-art caesium clocks.
Abstract: Extremely narrow optical resonances in cold atoms or single trapped ions can be measured with high resolution. A laser locked to such a narrow optical resonance could serve as a highly stable oscillator for an all-optical atomic clock. However, until recently there was no reliable clockwork mechanism that could count optical frequencies of hundreds of terahertz. Techniques using femtosecond-laser frequency combs, developed within the past few years, have solved this problem. The ability to count optical oscillations of more than 1015 cycles per second facilitates high-precision optical spectroscopy, and has led to the construction of an all-optical atomic clock that is expected eventually to outperform today's state-of-the-art caesium clocks.

2,612 citations

Journal ArticleDOI
TL;DR: In this paper, the authors report the first demonstration of a technique by which an optically thick medium may be rendered transparent by applying a temporally smooth coupling laser between a bound state of an atom and the upper state of the transition which is to be made transparent.
Abstract: We report the first demonstration of a technique by which an optically thick medium may be rendered transparent. The transparency results from a destructive interference of two dressed states which are created by applying a temporally smooth coupling laser between a bound state of an atom and the upper state of the transition which is to be made transparent. The transmittance of an autoionizing (ultraviolet) transition in Sr is changed from exp(-20) without a coupling laser present to exp(-1) in the presence of a coupling laser.

2,325 citations

Journal ArticleDOI
28 Mar 2008-Science
TL;DR: Repeated measurements during the past year yield a preliminary constraint on the temporal variation of the fine-structure constant α of α ofbatchmode, a regime of operation for atomic clocks based on optical transitions, promising even higher performance.
Abstract: Time has always had a special status in physics because of its fundamental role in specifying the regularities of nature and because of the extraordinary precision with which it can be measured. This precision enables tests of fundamental physics and cosmology, as well as practical applications such as satellite navigation. Recently, a regime of operation for atomic clocks based on optical transitions has become possible, promising even higher performance. We report the frequency ratio of two optical atomic clocks with a fractional uncertainty of 5.2 × 10–17. The ratio of aluminum and mercury single-ion optical clock frequencies νAl+/νHg+ is 1.052871833148990438(55), where the uncertainty comprises a statistical measurement uncertainty of 4.3 × 10–17, and systematic uncertainties of 1.9 × 10–17 and 2.3 × 10–17 in the mercury and aluminum frequency standards, respectively. Repeated measurements during the past year yield a preliminary constraint on the temporal variation of the fine-structure constant α of ![Formula][1] . [1]: /embed/tex-math-1.gif

1,335 citations

Journal ArticleDOI
TL;DR: A cross-phase modulation scheme that exhibits a giant, resonantly enhanced nonlinearity, along with vanishing linear susceptibilities, is analyzed and has possible applications in quantum nondemolition measurements and for quantum logic gates.
Abstract: We analyze a cross-phase modulation (XPM) scheme that exhibits a giant, resonantly enhanced nonlinearity, along with vanishing linear susceptibilities The proposed atomic system uses an electromagnetically induced transparency and is limited only by two-photon absorption We predict dramatic improvement by several orders of magnitude for conditional phase shifts in XPM, and the system has possible applications in quantum nondemolition measurements and for quantum logic gates

972 citations