title “when freezing cold is not cold enough - new forms of matter close to absolute zero...
TRANSCRIPT
![Page 1: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/1.jpg)
“When freezing cold is not cold enough - new forms of matter close
to absolute zero temperature”Wolfgang Ketterle
Massachusetts Institute of TechnologyMIT-Harvard Center for Ultracold Atoms
9/2/09Meridian Lecture
Space Telescope Science InstituteBaltimore
![Page 2: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/2.jpg)
Quantum Gases
The coldest matterin the universe
![Page 3: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/3.jpg)
What is temperature?
A measure of energy
One form of energy is motion(kinetic energy).
![Page 4: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/4.jpg)
Cold particles move slowly
Hot particlesare fast
![Page 5: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/5.jpg)
What is the lowest temperatures possible?
![Page 6: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/6.jpg)
Zero degree Kelvin(-273 degrees Celsius,
-460 degrees Fahrenheit) is the zero point
for energy
![Page 7: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/7.jpg)
The highest temperature is infinite
(In principle it is possible for particles to have arbitrarily high kinetic energies –until they become so heavy (due to E=mc2) that they from a black hole – at the Planck temperature of 1032 K)
![Page 8: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/8.jpg)
What is the differencein temperature between
summer and winter?
20 %
![Page 9: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/9.jpg)
How cold is interstellar space?
3 K
![Page 10: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/10.jpg)
How cold is itin our laboratories?
Nanokelvin:A billion times
colder than interstellarspace
![Page 11: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/11.jpg)
Why can you makenew discoveries
at cold temperatures?
![Page 12: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/12.jpg)
![Page 13: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/13.jpg)
What happens to atomsat low temperatures?
They slow down600 mph (300 m/sec) 1 cm/sec
They march in lockstep
![Page 14: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/14.jpg)
Matter made of waves!
![Page 15: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/15.jpg)
![Page 16: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/16.jpg)
Energy
Pop
ulat
ion
per
ener
gy s
tate
What is Bose Einstein Condensation?
T=Tc
Bose-Einstein distribution
![Page 17: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/17.jpg)
Energy
Pop
ulat
ion
per
ener
gy s
tate
What is Bose Einstein Condensation?
Bose-Einstein distribution
T<Tc
Condensate!
![Page 18: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/18.jpg)
Energy
Pop
ulat
ion
per
ener
gy s
tate
What is Bose Einstein Condensation?
Bose-Einstein distribution
T<Tc
Condensate!
![Page 19: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/19.jpg)
Laser lightOrdinary light
Photons/atoms moving randomly Photons/atoms are one big wave
![Page 20: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/20.jpg)
* 1925
![Page 21: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/21.jpg)
)(n1
1)( TkBe
1
1
TkBe
Max Planck
Black-Body Radiation“Photons”
Gases (Atoms and Molecules)
![Page 22: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/22.jpg)
The cooling methods
• Laser cooling• Evaporative cooling
![Page 23: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/23.jpg)
Hot atoms
![Page 24: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/24.jpg)
Hot atoms
Laser beams
![Page 25: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/25.jpg)
Hot atoms
Laser beams
Fluorescence
![Page 26: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/26.jpg)
Laser beams
Fluorescence
If the emitted radiation is blue shifted (e.g. by the Doppler effect) ….
![Page 27: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/27.jpg)
Cold atoms: 10 – 100 K
Laser beams
Fluorescence
Chu, Cohen-Tannoudji, Phillips, Pritchard, Ashkin, Lethokov, Hänsch, Schawlow, Wineland …
![Page 28: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/28.jpg)
2.5 cm
Laser cooling
![Page 29: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/29.jpg)
![Page 30: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/30.jpg)
Evaporative cooling
![Page 31: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/31.jpg)
Phillips et al. (1985)Pritchard et al. (1987)
![Page 32: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/32.jpg)
![Page 33: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/33.jpg)
One challenge …
experimental complexity
![Page 34: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/34.jpg)
Sodium laser cooling experiment (1992)
![Page 35: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/35.jpg)
Sodium BEC I experiment (2001)
![Page 36: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/36.jpg)
Dan Kleppner Tom Greytak Dave Pritchard
![Page 37: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/37.jpg)
Dan Kleppner
Dave Pritchard
Eric Cornell Carl WiemanWolfgang Ketterle
Bill PhillipsPhD
PhD
Postdoc
Under-graduate
PhD
RandyHulet
PhD
Norman Ramsey
PhD
I.I. Rabi
PhD
Postdoc
![Page 38: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/38.jpg)
Key factors for success:• Funding• Technical infrastructure• Excellent collaborators• Tradition and mentors
![Page 39: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/39.jpg)
How do we show that the Bose-Einstein
condensate has very low energy?
![Page 40: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/40.jpg)
The condensate• a puff of gas• 100,000 thinner than air• size comparable to the thickness of a hair• magnetically suspended in an ultrahigh vacuum chamber
![Page 41: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/41.jpg)
How to measure temperature?
Kinetic energy mv2/2 = kBT/2
Gas Effusive atomic beam
![Page 42: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/42.jpg)
How to measure temperature?
Kinetic energy mv2/2 = kBT/2
Gas Effusive atomic beam
![Page 43: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/43.jpg)
CCD
![Page 44: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/44.jpg)
CCD
Ballistic expansion: direct information about velocity distribution
![Page 45: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/45.jpg)
CCD
Absorption image: shadow of atoms
Ballistic expansion: direct information about velocity distribution
![Page 46: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/46.jpg)
The shadow of a cloud of bosonsas the temperature is decreased
(Ballistic expansion for a fixed time-of-flight)
Temperature is linearly related to the rf frequency which controls the evaporation
![Page 47: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/47.jpg)
Distribution of the times when data images were takenduring one year between 2/98-1/99
![Page 48: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/48.jpg)
Key factors for success:• Some funding• Technical infrastructure• Excellent collaborators• Tradition and mentors
![Page 49: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/49.jpg)
Key factors for success:• Some funding• Technical infrastructure• Excellent collaborators• Tradition and mentors• Physical endurance
![Page 50: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/50.jpg)
How can you prove that atoms march in lockstep?
Atoms are one single waveAtoms are coherent
![Page 51: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/51.jpg)
One paint ball on a white wallTwo
Paint does not show wave properties
![Page 52: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/52.jpg)
One laser beam on a white wall
Light shows wave properties
![Page 53: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/53.jpg)
One laser beam on a white wallTwo
Fringe pattern:Bright-dark-bright-dark
Light shows wave properties
![Page 54: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/54.jpg)
![Page 55: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/55.jpg)
Two condensates ...
50 m
![Page 56: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/56.jpg)
Interference of two Bose-Einstein condensates
Andrews, Townsend, Miesner, Durfee, Kurn, Ketterle, Science 275, 589 (1997)
![Page 57: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/57.jpg)
![Page 58: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/58.jpg)
How do we show that the gas is superfluid?
![Page 59: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/59.jpg)
![Page 60: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/60.jpg)
![Page 61: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/61.jpg)
Rigid body:
![Page 62: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/62.jpg)
![Page 63: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/63.jpg)
![Page 64: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/64.jpg)
Vortices in nature
![Page 65: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/65.jpg)
![Page 66: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/66.jpg)
![Page 67: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/67.jpg)
Spinning a Bose-Einstein condensate
Rotatinggreen laser beams
The rotating bucket experiment with a superfluid gas 100,000 thinner than air
Two-component vortex Boulder, 1999Single-component vortices Paris, 1999 Boulder, 2000 MIT 2001 Oxford 2001
J. Abo-Shaeer, C. Raman, J.M. Vogels,W.Ketterle, Science, 4/20/2001
![Page 68: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/68.jpg)
BEC on a microchip
Current Research
![Page 69: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/69.jpg)
Loading sodium BECs into atom chipswith optical tweezers
BECproductionBEC
arrival
44 cm
T.L.Gustavson, A.P.Chikkatur, A.E.Leanhardt, A.Görlitz, S.Gupta, D.E.Pritchard, W. Ketterle, Phys. Rev. Lett. 88, 020401 (2002).
Atom chip with waveguides
![Page 70: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/70.jpg)
![Page 71: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/71.jpg)
Splitting of condensates
15ms Expansion
Two condensates
1mm
One trappedcondensate
![Page 72: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/72.jpg)
Trapped 15ms expansion
1mm
Two condensates
Splitting of condensates
![Page 73: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/73.jpg)
Two condensates
Splitting of condensates
Y. Shin, C. Sanner, G.-B. Jo, T. A. Pasquini, M. Saba, W. Ketterle, D. E. Pritchard, M. Vengalattore, and M. Prentiss: Phys. Rev. A 72, 021604(R) (2005).
![Page 74: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/74.jpg)
Two condensates
Splitting of condensates
The goal:Atom interferometry:Matter wave sensors
Use ultracold atoms to sense
Rotation NavigationGravitation Geological exploration
![Page 75: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/75.jpg)
Cold moleculesCold fermions
Current Research
![Page 76: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/76.jpg)
Can electrons form a Bose-Einstein condensateand become superfluid (superconducting)?
Two kinds of particles• Bosons: Particles with an even number of protons, neutrons and electrons• Fermions: odd number of constituents
Only bosons can Bose-Einstein condense!
![Page 77: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/77.jpg)
![Page 78: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/78.jpg)
Can electrons form a Bose-Einstein condensateand become superfluid (superconducting)?
Two kinds of particles• Bosons: Particles with an even number of protons, neutrons and electrons• Fermions: odd number of constituents
Only bosons can Bose-Einstein condense!
How can electrons (fermions) condense?
They have to form pairs!
![Page 79: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/79.jpg)
Can we learn something aboutsuperconductivity
of electrons from cold atoms?
Yes, by studying pairing and superfluidity of atoms with an odd number of protons,
electrons and neutrons
![Page 80: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/80.jpg)
M.W. Zwierlein, C. A. Stan, C. H. Schunck,S.M. F. Raupach, S. Gupta, Z. Hadzibabic,W.K., Phys. Rev. Lett. 91, 250401 (2003)
BEC of Fermion Pairs (“Molecules”)
Boulder Nov ‘03Innsbruck Nov ‘03, Jan ’04MIT Nov ’03Paris March ’04Rice, Duke
These days: Up to 10 million condensed molecules
![Page 81: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/81.jpg)
Atomic Bose-Einsteincondensate (sodium)
Molecular Bose-Einsteincondensate (lithium 6Li2)
Pairs of fermionicatoms (lithium-6)
Gallery of superfluid gases
![Page 82: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/82.jpg)
Ultracold atomsA “toolbox” for designer matter
Normal matter• Tightly packed atoms• Complicated Interactions• Impurities and defects
![Page 83: Title “When freezing cold is not cold enough - new forms of matter close to absolute zero temperature” Wolfgang Ketterle Massachusetts Institute of Technology](https://reader038.vdocuments.us/reader038/viewer/2022110213/56649cb85503460f9497e022/html5/thumbnails/83.jpg)
Matter of ultracold atoms• 100 million times lower density• Interactions understood and controlled• no impurities• exact calculations possible
Ultracold atomsA “toolbox” for designer matter
Need 100 million times colder temperatures