PPT file - Laboratori Nazionali di Frascati

Atom Interferometers and Atomic Clocks:
From Ground to Space
Guglielmo M. Tino
Università degli Studi di Firenze - Dipartimento di Fisica, LENS
Istituto Nazionale di Fisica Nucleare - Sezione di Firenze
G.M. Tino, FPS-06, LNF, 22/3/2006
Laser cooling of atoms
nL
v
nL
Lab ref. frame
nL(1-v/c)
Idea:
T.W. Hänsch, A. Schawlow, 1975
Exp. demonstration:
S. Chu et al., 1985
nL(1+v/c)
Atom ref. frame
Sr MOT
LENS, Firenze
2 8
I / I v = - v
h

F (v)
4 2 c2  [1 (2 )2]2
L
0
G.M. Tino, FPS-06, LNF, 22/3/2006
Laser cooling: temperatures
Atomic Temperature : kBT = Mv2rms
k BT D 
Minimum temperature for Doppler cooling:
Single photon recoil temperature:
k BT r 
1  hn L 
M c 

h
2
2

Examples:
Na
Rb
Cs
TD
240 mK
120 mK
120 mK
Tr
2.4 mK
360 nK
200 nK
G.M. Tino, FPS-06, LNF, 22/3/2006
The Nobel Prize in Physics 1997
G.M. Tino, FPS-06, LNF, 22/3/2006
The Nobel Prize in Physics 2001
G.M. Tino, FPS-06, LNF, 22/3/2006
Atom optics
Atomic beam
Oven
lenses
laser
atom laser
atom
mirrors
laser
atom
beam-splitters
laser
interferometers
G.M. Tino, FPS-06, LNF, 22/3/2006
Atom Michelson Interferometer on a Chip
Using a Bose-Einstein Condensate
Ying-Ju Wang, Dana Z. Anderson, Victor M. Bright, Eric A. Cornell,
Quentin Diot, Tetsuo Kishimoto, Mara Prentiss, R. A. Saravanan,
Stephen R. Segal, Saijun Wu, Phys. Rev. Lett. 94, 090405 (2005)
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic clocks
G.M. Tino, FPS-06, LNF, 22/3/2006
The measurement of time
OSCILLATOR
Accuracy
Stability


COUNTER
realization of the standard
stability of the frequency: depends on
n 0
n0
of the oscillator
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic clocks
The definition of the second
n.t = 1
The second is the duration of
9 192 631 770 periods of the
radiation corresponding to the
transition between the two
hyperfine levels of the ground
state of the 133Cs atom
(13th CGPM, 1967)
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic fountain clock
NIST-F1
G.M. Tino, Firenze, 11/12/2003
G.M. Tino,
FPS-06, LNF, 22/3/2006
Cold Atoms Clocks in Space
• Interrogate fast (hot) atoms over
long distances  T = 10 ms
• Use laser cooled atoms,
limitation due to the presence of
gravity  T = 1 s
• Use laser cooled atoms in
microgravity  T = 10 s
PHARAO
C. Salomon et al.,
C.R. Acad. Sci. 2, 1313 (2001)
G.M. Tino, FPS-06, LNF, 22/3/2006
Accuracy of the atomic time
ACCURACY OF THE ATOMIC TIME
RELATIVE ACCURACY
1x10
-9
1x10
-10
1x10
-11
1x10
-12
1x10
-13
1x10
-14
10
-15
1x10
-16
10
-17
1950
Microwave clocks
Slope: gain of 10 every 10 years
Optical clocks
NPL
NBS
LSRH
Ca PTB
PTB
NRC
NBS
VNIIFTRI
H MPQ
PTB
NIST
NPL
PTB NIST
SYRTE
Cold atoms
1960
1970
1980
1990
2000
?
2010
YEAR
from C. Salomon
G.M. Tino, FPS-06, LNF, 22/3/2006
Optical clocks: Towards 10-18-10-19
• Narrow optical transitions
no ~ 1 Hz, n0 ~ 1015 Hz
y
Noise
 Q Signal
n
1
n0
N atom
Tcycle
1
2 average Cfringe
Trapped ions: Hg+, In+, Sr+, Yb+,…
• Candidate atoms
Cold neutral atoms: H, Ca, Sr, Yb,…
(Fermions?)
• Direct optical-mwave connection by optical frequency comb
Th. Udem et al., Nature 416 , 14 march 2002
G.M. Tino, FPS-06, LNF, 22/3/2006
G.M. Tino, FPS-06, LNF, 22/3/2006
Ca clock example
From L. Hollberg, Hyper symposium 2002
G.M. Tino, FPS-06, LNF, 22/3/2006
87Sr
optical clock
• Method: (H. Katori)
Interrogate atoms in optical lattice without frequency shift
• Long interaction time
• Large atom number (108)
• Lamb-Dicke regime
Excellent frequency stability
• Small frequency shifts:
• No collisions (fermion)
• No recoil effect (confinement below optical wavelength)
• Small Zeeman shifts (only nuclear magnetic moments)…
G.M. Tino, FPS-06, LNF, 22/3/2006
Towards a Sr clock – The experiment in Firenze
Firenze 2003, Magneto-optical trapping of all Sr isotopes
0.20
86
0.18
88
Sr
87
Sr
Sr
• Optical clocks using visible
intercombination lines
1S
0
1S
0
1S
0
Fluorescence signal (V)
0.16
0.14
- 3P1 (7.5 kHz)
- 3P0 (1 mHz, 87Sr)
- 3P2 (0.15 mHz)
Optical trapping in Lamb-Dicke regime
with negligible change of clock frequency
Comparison with different ultra-stable clocks
(PHARAO/ACES) PHARAO
G. Ferrari, P.Cancio, R. Drullinger, G. Giusfredi, N. Poli, M. Prevedelli, C. Toninelli and
G.M. Tino, Phys. Rev. Lett. 91, 243002 (2003)
0.12
0.10
84
0.08
Sr
0.06
0.04
-400
-200
0
200
Laser detuning (MHz)
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic clocks
•
•
•
•
•
Location finding
Precision navigation and navigation in outer space
Variability of Earth’s rotation rate and other periodic phenomena
Earth’s crustal dynamics
Secure telecommunications
•
•
•
•
•
Very Long Baseline Interferometry (VLBI)
Spectroscopy
Expression of other physical quantities in terms of time
Tests of constancy of fundamental constants
Tests of the special and general theories of relativity
G.M. Tino, FPS-06, LNF, 22/3/2006
Atom Interferometers
G.M. Tino, FPS-06, LNF, 22/3/2006
Quantum interference
path I
amplitude AI
Initial state
|yi
Final state
path II
amplitude AII
|yf
Interference of transition amplitudes
P(|yi|yf) = |AI + AII|2 = |AI|2 + |AII|2 + 2 Re(AI AII*)
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic clocks: Interference fringes
G.M. Tino, FPS-06, LNF, 22/3/2006
Time-domain Ramsey-Bordé interferences
with cold Ca atoms (PTB)
G.M. Tino, FPS-06, LNF, 22/3/2006
Atom Interferometry
Atom interferometer
Flux

Phase difference
  1  2
atomic flux at exit port 1
at exit port 2
G.M. Tino, FPS-06, LNF, 22/3/2006
Matter wave sensors
accelerations:
 acc  k T
2
drift
a
2
a
rotations:

 mat  c 
~    1011  1017
 ph  v at 
2 mat
 rot  2
A 
h
 mat m at    c
10
~
 5  10
 ph
h
G.M. Tino, FPS-06, LNF, 22/3/2006
SYRTE cold atom gyroscope
50 cm
30 cm
One pair of Raman
lasers switched on
3 times
Detections

Launching velocity: 2.4 m.s-1
Maximum interaction time : 90 ms
3 rotation axes
2 acceleration axes
Cycling frequency 2Hz
Magneto-Optical Traps
Expected sensitivity (106 at):
• gyroscope : 4 10-8 rad.s-1.Hz-1/2
• accelerometer : 3 10-8 m.s-2.Hz-1/2
G.M. Tino, FPS-06, LNF, 22/3/2006
IQO Cold Atom Sagnac Interferometer
Interferometer

/2
Preparation /2
Detection
3 mm
15 cm
A
MOT 2
MOT 1
C. Jentsch, T. Müller, E. Rasel, and W. Ertmer, Gen. Rel. Grav, 36, 2197 (2004)
& Adv. At. Mol. Physics
G.M. Tino, FPS-06, LNF, 22/3/2006
MAGIA
Misura Accurata di G mediante Interferometria Atomica
• Measure g using free falling
atoms and atom interferometry
• Add known source masses
• Measure change of g
aM
g
Determine G
G.M. Tino, in “2001: A Relativistic Spacetime Odyssey”, World Scientific (2003)
M. Fattori, G. Lamporesi, T. Petelski, J. Stuhler, G.M. Tino, Phys. Lett. A 318, 184 (2003)
http://www.fi.infn.it/sezione/esperimenti/MAGIA/home.html
G.M. Tino, FPS-06, LNF, 22/3/2006
MAGIA
Misura Accurata di G mediante Interferometria Atomica
I
II
z1
1
1
z2
2
2
In collaboration with LNF, Frascati
http://www.fi.infn.it/sezione/esperimenti/MAGIA/home.html
G.M. Tino, FPS-06, LNF, 22/3/2006
MAGIA: Firenze atom gravity gradiometer apparatus
Source masses and support
Laser and optical system
Phase locked lasers for Raman transitions
L. Cacciapuoti et al., Rev. Scient. Instr. 76, 053111 (2005)
G.M. Tino, FPS-06, LNF, 22/3/2006
MAGIA: first results
G.M. Tino, FPS-06, LNF, 22/3/2006
Precision Measurement of Gravity at
Micrometer Scale using Ultracold Sr Atoms
mirror
n = m g  /2 h
red MOT
beams
trapped
atoms
g
probe
beam
optical lattice
beam
CCD
camera
• G. Ferrari et al., 2006, to be published
G.M. Tino, FPS-06, LNF, 22/3/2006
Test of the gravitational 1/r2 law in the sub-mm range
with atom interferometry sensors (Casimir?)
95% confidence level constraints on a Yukawa violation
of the gravitational inverse-square law. The vertical axis
represents the strength of a deviation relative to that of
Newtonian gravity while the horizontal axis designates its
characteristic range. The yellow region has been excluded
(From S. J. Smullin et al., 2005)
mirror
a = 2Grd
r
trapped
atoms
red MOT
beams
g
Example:
rAu 19 g/cm3
d  200 mm
a2x
10-9
ms-2
probe
beam
CCD
camera
optical lattice
beam
-d-
n = m g  /2 h
• G.M. Tino, in “2001: A Relativistic Spacetime Odyssey”, Firenze, 2001, World Scientific (2003)
• G.M. Tino, Nucl. Phys. B 113, 289 (2002)
• G. Ferrari et al., 2006, to be published
G.M. Tino, FPS-06, LNF, 22/3/2006
From Earth Laboratories to Space
G.M. Tino, FPS-06, LNF, 22/3/2006
Atomic Clock Ensemble in Space
H= 400 km
V=7 km/s
T= 5400 s
• A cold atom clock in space
• Worldwide access
• Fundamental physics tests
PHARAO : Cold Atom Clock in Space. CNES (France)
A. Clairon, P. Laurent, P. Lemonde, M. Abgrall, S. Zhang, C. Mandache, F.
Allard, M. Maximovic, F. Pereira, G. Santarelli, Y. Sortais, S. Bize, H.
Marion, D. Calonico, (BNM-LPTF), N. Dimarcq (LHA), C. Salomon (ENS)
SHM : Space Hydrogen Maser. ON (Switzerland)
L. Jornod, D. Goujon, L.G. Bernier, P. Thomann, G. Busca
MWL : Microwave link. Kayser-Threde-Timetech (Germany)
W. Schaefer, S. Bedrich
ACES is open to any interested scientific user
W. Knabe, P. Wolf, L. Blanchet, P. Teyssandier, P. Uhrich, A. Spallici
New members :
2001: UWA (Australia), A. Luiten, M. Tobar, J. Hartnett, R. Kovacich
2002: LENS (Italy), G.M. Tino, G. Ferrari, L. Cacciapuoti
ESA: MSM
Stephen Feltham
CNES:
C. Sirmain + team of 20 engineers at CST, Toulouse
Support: ESA, CNES, BNM, CNRS
G.M. Tino, FPS-06, LNF, 22/3/2006
ACES ON COLUMBUS EXTERNAL
PLATFORM
ACES
M = 227 kg
P = 450 W
Launch date : 2009
Mission duration : 18 months
G.M. Tino, FPS-06, LNF, 22/3/2006
ACES objectives
L. Blanchet, C. Salomon, P. Teyssandier, and P. Wolf, A&A 370, 320 (2001)
G.M. Tino, FPS-06, LNF, 22/3/2006
ESA-AO-2004
Life and Physical Sciences and Applied Research Projects
G.M. Tino, FPS-06, LNF, 22/3/2006
PARCS
Primary Atomic Reference Clock in Space
G.M. Tino, FPS-06, LNF, 22/3/2006
HYPER
Mapping Lense-Thirring
effect close to the Earth

Improving knowledge of
fine-structure constant
Differential measurement between two
atom gyroscopes and a star tracker
orbiting around the Earth
~h/m
Testing EP with
microscopic bodies
Atomic gyroscope
control of a satellite
http://sci.esa.int/home/hyper/index.cfm
G.M. Tino, FPS-06, LNF, 22/3/2006
ESA-AO-2004 AI
G.M. Tino, FPS-06, LNF, 22/3/2006
Laser Cooled Atom (LCA) Sensor
for Ultra-High-Accuracy Gravitational Acceleration
and Rotation Measurements
in response to ESA ITT No. AO-1-4477/03/NL/CH
G.M. Tino, FPS-06, LNF, 22/3/2006
SpacePart ‘03
Prototype field ready sensor
W.W. Hansen Experimental Physics Laboratory, Stanford, CA 94305
Sensor head
Sensor optomechanics
From M. Kasevich talk at
SpacePart '03 Conference
Washington D.C., December 10th - 12th, 2003.
Laser system
G.M. Tino, FPS-06, LNF, 22/3/2006
JPL
http://horology.jpl.nasa.gov/quantum/atominterferometry.html
G.M. Tino, FPS-06, LNF, 22/3/2006
BEC in space
G.M. Tino, FPS-06, LNF, 22/3/2006
DC-DC
transformer
Computer
control
Laser
pumps
µ-metal shielding
Battery pack
From E. Rasel, 2005
G.M. Tino, FPS-06, LNF, 22/3/2006
G.M. Tino, FPS-06, LNF, 22/3/2006
Applications of new quantum sensors
based on atom interferometry
• Measurement of fundamental constants
G

• New definition of kg
• Test of equivalence principle
• Short-distances forces measurement
• Search for electron-proton charge inequality
• New detectors for gravitational waves ?
geophysics
• Development of transportable
atom interferometers
space
G.M. Tino, FPS-06, LNF, 22/3/2006
Future prospects:
Atomic clocks
• New optical clocks with fractional stability ~ 10-17-10-19
• mm-scale positioning and long-distance clock syncronization
• Very large baseline interferometry (VLBI) and geodesy
• Search for variation of fundamental constants
• Tests of SR and GR in Earth orbit (ACES, OPTIS)
• Improved tests of GR in solar orbit: Shapiro delay, red shift, …
G.M. Tino, FPS-06, LNF, 22/3/2006
Conclusions
• New atomic quantum devices can be developped with unprecedented sensitivity
using ultracold atoms and atom optics
• Applications: Fundamental physics, Earth science, Space research, Commercial
• Well developped laboratory prototypes
• Work in progress for transportable/space-compatible systems
G.M. Tino, FPS-06, LNF, 22/3/2006
Fine
G.M. Tino, FPS-06, LNF, 22/3/2006
LINKS
G.M. Tino, FPS-06, LNF, 22/3/2006
h/m and fine structure constant
S. Chu et al., 2002
G.M. Tino, FPS-06, LNF, 22/3/2006
Unit of mass
The kilogram is the unit of mass;
it is equal to the mass of the
international prototype of the
kilogram (1st CGPM, 1889)
Goal: Redefinition of kg on microscopic
quantities with accuracy better than 10-8
Idea: Watt-balance compares electrical and
mechanical realization of Watt
UI  m g v
Watt balance groups
working at
NPL (UK),
NIST (USA),
METAS (Switzerland),
BNM (France)
I

 mg
z
U


 v
t
z
G.M. Tino, FPS-06, LNF, 22/3/2006
Tests of weak equivalence principle
Best tests so far: EOT-Wash group (Adelberger, Gundlach),
See “http://www.npl.washington.edu/eotwash/”
Long range EP tested at the level of 10-13
Prospects
Space:
MICROSCOPE  10-15
STEP
Atoms:
 10-18
S, et al. PRL. 93, 240404 (2004)
)
• different isotopes, e.g. 85Rb vs 87Rb ( Fray
g/g=(0.4+/-1.2)x10-7
• different atoms, e.g. Rb vs Cs
-12 - 10-13

10
40
• bosons vs fermions, e.g. Rb vs K
• different spins
• anti-matter (?)
G.M. Tino, FPS-06, LNF, 22/3/2006
Test of equivalence principle for anti-matter
• Compare g
H
H
• Steps:
 anti-H production (ATHENA, ATRAP)
 anti-H selective state population
 anti-H cooling
 anti-H trapping


5
4
5
4
3s1/2
3p 3/21/2
1
2s1/2
177 MHz
3/
2
2p 1/2
0
24 MHz
10968 MHz
59 MHz
243 nm
121.6 nm
243 nm
1s1/2
1
1420 MHz
0
H levels
partial scheme
(not to scale)
 g measurement:
- Time of flight
g/g  10-3 ?
- Atom interferometry
• Raman transitions between 2S HFS sublevels
• 2Shigh-P levels transitions
g/g  10-9 ?
(T. Heupel et al., Europhys. Lett. 57, 158 (2002))
G.M. Tino, FPS-06, LNF, 22/3/2006
Search for electron-proton charge inequality
• Electrostatic, ferromagnetic, diamagnetic levitation
Millikan (1935), Morpurgo (1966-1984), Braginsky (1970), Stover (1967), Rank (1968), LaRue (1979)
• Gas flow
Piccard and Kessler (1925), Hillas & Cranshaw (1960), King (1960)
• Acoustic cavity
Dylla and King (1973)
• Atomic and molecolar beams
Hughes (1957), Chamberlain & Hughes (1963), Fraser (1965), Shapiro (1957), Shull (1967)
Present limit
ep< 1x10-21 e
(From G. Carugno and G. Ruoso)
G.M. Tino, FPS-06, LNF, 22/3/2006
ep = qe+ qp; qn ; qn
Neutralità materia
Motivazioni: digressione storica
Einstein (1929)
Spiegare campi magnetici terra e sole
ep + rotazione -> i -> B
si aspettava ep= 3x10-19 e
Limiti su qn e qn
Se C e CPT conservati
da qn = qe + qp + qn ricavo limiti
Attualmente
qn < 10-21 e
Esp. con fasci di neutroni termici (1988)
Bondi - Lyttleton (1959); Hoyle (1960) q < 10-15 e
n
-18
se ep~ 2x10 e => espansione universo Da astrofisica, Barbiellini - Cocconi (1987)
Chiu - Hoffmann (1964)
Indipendenza della carica dell’elettrone
dalla velocità e trasformazioni di Lorentz
Feinberg - Goldhaber (1959);
Gell-Mann - Nambu (1960)
ep ≠ 0 per spiegare leggi di
conservazione (es. numero barionico)
qe (v)  qe (0)[1 a(v /c) 2 ]
Con atomi di vario Z miglioro limite
(Da G. Carugno and G. Ruoso)
G.M. Tino, FPS-06, LNF, 22/3/2006
Search for electron-proton charge
inequality
ep< 1x10-25 e ?
G.M. Tino, FPS-06, LNF, 22/3/2006
Gravitational wave detection by atom
interferometry
1E-16
1E-17
h (1/Sqrt(Hz))
1E-18
1E-19
1E-20
1E-21
1E-22
1E-23
Virgo
1E-24
1E-3 0,01
0,1
1
10
100
1000 10000
/2 (Hz)
Presentation at 2004 Aspen Winter College on Gravitational Waves:
See http://www.ligo.caltech.edu/LIGO_web/Aspen2004/pdf/vetrano.pdf
See also:
Chiao RY, Speliotopoulos AD, J. Mod. Opt. 51, 861 (2004)
A. Roura, D.R. Brill, B.L. Hu, C.W. Misner, gr-qc/0409002
G.M. Tino, FPS-06, LNF, 22/3/2006
Sources - Detectors
h [1/sqrt Hz]
SN core
collapse
1
2
3
-18
LISA
LIGO – Virgo
A.I.
1
Coalescence of
massive BH
-20
2
3
ms
Pulsars
(1 y)
-22
Slow
Pulsars
(1 y)
Galactic binaries
NS-NS and
BH-BH Coalescence
LMXRBs
&
Perturbed
“newborn”NS
-24
-4
10
-2
10
0
10
2
10
4
10
f [Hz]
G.M. Tino, FPS-06, LNF, 22/3/2006
Gravimeters
A. Peters, K.Y. Chung and S. Chu,
Nature 400, 849 (1999)
Resolution: 3x10-9 g after 1 minute
Absolute accuracy: g/g<3x10-9
Comparison between instruments
Resolution g/g
Accuracy g/g
Or Repeatibility
Measurement
Size and Weight
Spring gravimeter(1)
Optical interferometry
dropping gravimeter(2,3)
Superconducting
gravimeter(3,4)
Atom interferometry
gravimeter(5)
5 x 10-9
only for short periods
and distances
1 x 10-8/Hz
1 x 10-8/Hz
2 x 10-8 in 1.3 s
0.5 x 10-6
only for short periods
and distances
4 x 10-9
1 x 10-9
1 x 10-9
Relative
Absolute
Relative
Absolute
No field operation
estimated 1 m3
250 kg
21.5 x 22 x 31 cm
9 kg
3
1.5 m
320 kg
temperature and
thermal drift
random drift
magnetic and
magnetic and
?
Clibration varies in
electrostatic effects
electrostatic effects
time and with position
(1) www.LaCosteRomberg.com
(2) www.microgsolutions.com
(3)O. Francis, T.M. Niebauer, G. Sasagawa, F. Klopping, and G. Gschwind, “Calibration of a superconducting gravimeter by
comparison with an absolute gravimeter FG5 in Boulder”, Geoph. Res. Lett.25 (1998) 1075-1078.
(4) J.M. Goodkind “The superconducting gravimeter”, Rev. Scient. Instr., 70 (1999) 4131-4152.
(5) A. Peters, K.Y. Chung, and S. Chu “Measurement of gravitational acceleration by dropping atoms”, 400 (1999) 849-852.
Error sources
G.M. Tino, FPS-06, LNF, 22/3/2006
Gravimeter application in geophysics
Gravimetric measurements at Etna Pizzi DeNeri site during a 48-h-long
period encompassing the beginning of the 2002-2003 eruption
(Branca et al. Geoph. Res. Lett. 30 2077 (2003))
G.M. Tino, FPS-06, LNF, 22/3/2006
Gravimeter Application
Geophysical research
Monitoring of magma migration in active volcanic areas
Detection of vertical crustal motion in seismogenic areas
Post glacial rebound studies
Measuring uplift in subduction areas
Earthquake (strain accumulation in tectonic areas during interseismic phase)
Calibrating measurement made by other techniques: height measurements, relative gravimeter
Environmental monitoring
Water table monitoring in deep and/or multiple acquifers
Monitoring of mining effect
Slope and earth fill dam stability
Global sea level studies for earth warming assessment
On site inspection of sites for nuclear test or else.
Mineral exploration
G.M. Tino, FPS-06, LNF, 22/3/2006
Gradiometer applications
Airborne gravity measurement for
oil and mineral exploration
hazard investigation
Satellite gravity meausrement :
GOCE project
GRACE Project
Gravity gradiometry gives higher resolution in
Monitoring of anomalies
Data processing
Joint gravimetric-seismological data inversion
Gradiometer based on absolute Gravimeter
combines complementary range of sensitivity for different mass/distance source
Tensorometer
G.M. Tino, FPS-06, LNF, 22/3/2006
ACES: Relativity tests
G.M. Tino, FPS-06, LNF, 22/3/2006
Search for variation of 
G.M. Tino, FPS-06, LNF, 22/3/2006
Search for variation of 
G.M. Tino, FPS-06, LNF, 22/3/2006