Cold Atom experiments in Microgravity Our experiment requires good laser stability despite: - Gravity changes - Strong vibrations - Temperature fluctuations Airbus A300 0G : • 3 flight days • 31 parabolas per flight • 22s of microgravity per parabola • Between 1 and 3 campaigns per year. A compact and transportable cold atom accelerometer for space applications P.-A. Gominet 1,2 , B.Barrett 1,2 , B. Battelier 1 , N. Zahzam 3 , A. Landragin 4 and P. Bouyer 1 1 : LP2N (Laboratoire Photonique Numérique et Nanosciences), Université Bordeaux I, IOGS et CNRS, allée René Laroumagne, 33400, Talence, France – 2 : CNES, 18 Avenue Edouard Belin, 31400 Toulouse 3: ONERA, Chemin de la Hunière, 91761 Palaiseau – 4 : LNE-Syrte, Observatoire de Paris, 61 avenue de l'Observatoire, 75014 Paris. Forward : • A new titanium vacuum chamber : 19 viewports. • Dipole trap to reach T < 1 μK. • All fiber setup. • Test of the Weak Equivalence Principle with cold atoms [6]. • 3-axis cold atom accelerometer. • STE-QUEST: a Satellite mission to test the equivalence principle with very high precision [7]. (Pre-selected in ESA's Cosmic Vision Program) Applications of high resolution inertial sensors References [1] C.M. Will, Living Rev. Relativity, 9, 3 (2006). [2] J.G. Williams et al., Int. J. Mod. Phys. D, 7, 1129 (2009). [3] T.A. Wagner et al., Class.Quantum Grav., 29, 184002 (2012). [4] V. Ménoret et al, Optics Lett., 36, 4128 (2011). [5] R. Geiger et al., Nature Commun., 2, 474 (2011). [6] G. Varoquaux et al., NJP, 11, 113010 (2009). [7] STE-QUEST Mission. http://sci.esa.int/ste-quest (July 2011). ● First airborne matter-wave interferometer achieved with 87Rb. ● Correlation principle between a mechanical accelerometer (MA) and an atom interferometer (AI) [5]. ● Resolution 300 times below the vibration level in the plane! ➔ Hybrid Sensor performance : ~100μg T=1ms Phase Noise ~8rad ! Atomic Interferometer principle • Analogous to an optical Mach- Zehnder interferometer. • Stimulated Raman transitions are used to split and reflect the atoms. ● Laser phase is imprinted on the atomic wavefunction. - Interferometer output signal : = − (∆∅) - Interferometer phase shift resulting from acceleration of the atoms : ∆∅ = − ∙ ² → Atomic phase difference depends on the inertial field. • Raman beam induces two-photon transitions. • This changes both the internal and external state of the atoms. → Fluorescence detection system Rb 87 and K 39 structure Telecom-based dual-frequency laser source → We need a robust and compact laser source [4]. • We use optical fibers, frequency doubling of C-band telecom laser (1560 & 1534 nm to 780 & 767 nm) and RIO diode (10kHz linewidth). • Both lasers are phase-locked to an optical frequency comb: no relative frequency drifts. • Femto-second comb laser is specially designed for our fiber laser source in 0G flight. New Experimental Results in 39K • We have cooled 39K below 30 μK using ONLY sub-Doppler laser cooling techniques. STEP 1 : Coarse measurement with MA (fringe determination). STEP 2 : Fine measurement with AI. Parabolic flight campaigns organized by NOVESPACE at Bordeaux airport (France). ● Fundamental physics (on ground or in space) : test of the equivalence principle with 2 atoms ( and ). ● Industrial applications : Autonomous inertial navigation aboard aircrafts without drifts. Gravity surveys (geophysics, oil & mineral prospecting,…). T ~ 25 μK • We have also achieved the first 39K Ramsey fringes in the lab AND in the 0g plane. T = 10 ms T = 20 ms 2g 0g 2g RIO : laser diode -- OI : Optical Isolator -- PM : Phase Modulator -- PPLN : Periodically Poled Lithium Niobate crystal -- FC. : Fiber Combiner -- AOM : Acousto Optic Modulator -- EDFA : Erbium Doped Fiber Amplifier -- DM :Dichroic Mirror -- GM : Gold Mirror. Testing Weak Equivalence Principle (WEP) • Postulate (no demonstration) • Violation expected : incompatibility between general relativity and quantum mechanics [1] Need accurate measurement The best measurements : • Laser Lunar Ranging (LLR) [2] • Torsion balances [3] Violation at η = 10 -15 ? With cold atom interferometer: • Test at the quantum scale • Test with 2 different atoms (mass and composition) • Highly precise. Eötvös parameter : η = 10 -13 2g 0g 2g Parabola duration : 1 min
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Cold Atom experiments in Microgravity
Our experiment requires good laser stability despite:
- Gravity changes - Strong vibrations
- Temperature fluctuations
Airbus A300 0G :
• 3 flight days
• 31 parabolas per flight
• 22s of microgravity per parabola
• Between 1 and 3 campaigns per
year.
A compact and transportable cold atom accelerometer for space applications
P.-A. Gominet1,2, B.Barrett1,2, B. Battelier1, N. Zahzam3, A. Landragin4 and P. Bouyer1
1 : LP2N (Laboratoire Photonique Numérique et Nanosciences), Université Bordeaux I, IOGS et CNRS, allée René Laroumagne, 33400, Talence, France – 2 : CNES, 18 Avenue Edouard Belin, 31400 Toulouse 3: ONERA, Chemin de la Hunière, 91761 Palaiseau – 4 : LNE-Syrte, Observatoire de Paris, 61 avenue de l'Observatoire, 75014 Paris.
Forward :
• A new titanium vacuum chamber : 19 viewports.
• Dipole trap to reach T < 1 µK.
• All fiber setup.
• Test of the Weak Equivalence Principle with cold atoms [6].
• 3-axis cold atom accelerometer.
• STE-QUEST: a Satellite mission to test the equivalence principle with very high precision [7]. (Pre-selected in ESA's Cosmic Vision Program)
Applications of high resolution inertial sensors
References
[1] C.M. Will, Living Rev. Relativity, 9, 3 (2006). [2] J.G. Williams et al., Int. J. Mod. Phys. D, 7, 1129 (2009). [3] T.A. Wagner et al., Class.Quantum Grav., 29, 184002 (2012).
[4] V. Ménoret et al, Optics Lett., 36, 4128 (2011). [5] R. Geiger et al., Nature Commun., 2, 474 (2011). [6] G. Varoquaux et al., NJP, 11, 113010 (2009). [7] STE-QUEST Mission. http://sci.esa.int/ste-quest (July 2011).
● First airborne matter-wave interferometer achieved with 87Rb.
● Correlation principle between a mechanical accelerometer (MA) and an atom interferometer (AI) [5].
● Resolution 300 times below the vibration level in the plane!
➔ Hybrid Sensor performance : ~100µg
T=1ms Phase Noise ~8rad !
Atomic Interferometer principle
• Analogous to an optical Mach-Zehnder interferometer.
• Stimulated Raman transitions are used to split and reflect the atoms.
● Laser phase is imprinted on the atomic wavefunction.
- Interferometer output signal :
𝑷 = 𝑷𝟎 − 𝑨 𝒄𝒐𝒔(∆∅)
- Interferometer phase shift resulting from acceleration of the atoms :
∆∅ = 𝒌𝟏 − 𝒌𝟐 ∙ 𝒂𝑻²
→ Atomic phase difference depends on the inertial field.
• Raman beam induces two-photon
transitions.
• This changes both the internal
and external state of the atoms.
→ Fluorescence detection system
Rb87 and
K39 structure
Telecom-based dual-frequency laser source
→ We need a robust and compact laser source [4].
• We use optical fibers, frequency doubling of C-band telecom laser (1560 & 1534 nm to 780 & 767 nm) and RIO diode (10kHz linewidth).
• Both lasers are phase-locked to an optical frequency comb: no relative frequency drifts.
• Femto-second comb laser is specially designed for our fiber laser source in 0G flight.
New Experimental Results in 39K
• We have cooled 39K below 30 µK using ONLY
sub-Doppler laser cooling techniques.
STEP 1 : Coarse measurement with
MA (fringe determination).
STEP 2 : Fine measurement with AI.
Parabolic flight campaigns organized by NOVESPACE at Bordeaux airport (France).
● Fundamental physics (on ground or in space) : test of the
equivalence principle with 2 atoms ( 𝑹𝒃𝟖𝟕 and 𝑲𝟑𝟗 ).
● Industrial applications :
Autonomous inertial navigation aboard aircrafts without drifts.
Gravity surveys (geophysics, oil & mineral prospecting,…).
T ~ 25 µK
• We have also achieved the first 39K Ramsey fringes in the lab AND in the 0g
plane.
T = 10 ms T = 20 ms
2g 0g 2g
RIO : laser diode -- OI : Optical Isolator -- PM : Phase Modulator -- PPLN : Periodically Poled Lithium Niobate
crystal -- FC. : Fiber Combiner -- AOM : Acousto Optic Modulator -- EDFA : Erbium Doped Fiber Amplifier -- DM
:Dichroic Mirror -- GM : Gold Mirror.
Testing Weak Equivalence Principle (WEP)
• Postulate (no demonstration) • Violation expected : incompatibility between
general relativity and quantum mechanics [1]
Need accurate measurement
The best measurements :
• Laser Lunar Ranging (LLR) [2]
• Torsion balances [3]
Violation at η = 10-15?
With cold atom interferometer:
• Test at the quantum scale
• Test with 2 different atoms (mass and composition)
• Highly precise.
Eötvös parameter :
η = 10-13
2g 0g 2g
Parabola duration : 1 min
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