Physics:Atom interferometer

From HandWiki
Short description: Interferometer which uses the wave-like nature of atoms

An atom interferometer is an interferometer which uses the wave character of atoms. Similar to optical interferometers, atom interferometers measure the difference in phase between atomic matter waves along different paths. Today, atomic interference is typically controlled with laser beams.[1](pp420-1) Atom interferometers have many uses in fundamental physics including measurements of the gravitational constant, the fine-structure constant, the universality of free fall, and have been proposed as a method to detect gravitational waves.[2] They also have applied uses as accelerometers, rotation sensors, and gravity gradiometers.[3]

Overview

Interferometry splits a wave into two or more paths, then recombines the waves after interaction along one of the paths. Atom interferometer uses center of mass matter waves with short de Broglie wavelength.[4] [5] Some experiments are now even using molecules to obtain even shorter de Broglie wavelengths and to search for the limits of quantum mechanics.[6] In many experiments with atoms, the roles of matter and light are reversed compared to the laser based interferometers, i.e. the beam splitter and mirrors are lasers while the source instead emits matter waves (the atoms).

Interferometer types

A compact Magneto-optical Trap, the first step in generating an atom interferometer.

While the use of atoms offers easy access to higher frequencies (and thus accuracies) than light, atoms are affected much more strongly by gravity. In some apparatuses, the atoms are ejected upwards and the interferometry takes place while the atoms are in flight, or while falling in free flight. In other experiments gravitational effects by free acceleration are not negated; additional forces are used to compensate for gravity. While these guided systems in principle can provide arbitrary amounts of measurement time, their quantum coherence is still under discussion. Recent theoretical studies indicate that coherence is indeed preserved in the guided systems, but this has yet to be experimentally confirmed.

The early atom interferometers deployed slits or wires for the beam splitters and mirrors. Later systems, especially the guided ones, used light forces for splitting and reflecting of the matter wave.[7]

Examples

Group Year Atomic species Method Measured effect(s)
Pritchard 1991 Na, Na2 Nano-fabricated gratings Polarizability, index of refraction
Clauser 1994 K Talbot-Lau interferometer
Zeilinger 1995 Ar Standing light wave diffraction gratings
Helmke
Bordé 		1991 Ramsey–Bordé Polarizability,
Aharonov–Bohm effect: exp/theo [math]\displaystyle{ 0.99 \pm 0.022 }[/math],
Sagnac effect 0.3 rad/s/[math]\displaystyle{ \surd }[/math]Hz
Chu 1991
1998 		Na

Cs

Kasevich - Chu interferometer
Light pulses Raman diffraction 		Gravimeter: [math]\displaystyle{ 3 \cdot 10^{-10} }[/math]
Fine-structure constant: [math]\displaystyle{ \alpha\pm 1.5 \cdot 10^{-9} }[/math]
Kasevich 1997
1998 		Cs Light pulses Raman diffraction Gyroscope: [math]\displaystyle{ 2\cdot 10^{-8} }[/math]rad/s/[math]\displaystyle{ \surd }[/math]Hz,
Gradiometer:
Berman Talbot-Lau

History

Interference of atom matter waves was first observed by Immanuel Estermann and Otto Stern in 1930, when a sodium (Na) beam was diffracted off a surface of sodium chloride (NaCl).[8] The first modern atom interferometer reported was a double-slit experiment with metastable helium atoms and a microfabricated double slit by O. Carnal and Jürgen Mlynek in 1991,[9] and an interferometer using three microfabricated diffraction gratings and Na atoms in the group around David E. Pritchard at the Massachusetts Institute of Technology (MIT).[10] Shortly afterwards, an optical version of a Ramsey spectrometer typically used in atomic clocks was recognized also as an atom interferometer at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany.[11] The largest physical separation between the partial wave packets of atoms was achieved using laser cooling techniques and stimulated Raman transitions by Steven Chu and his coworkers in Stanford University.[12]

In 1999, the diffraction of C60 fullerenes by researchers from the University of Vienna was reported.[13] Fullerenes are comparatively large and massive objects, having an atomic mass of about 720 u. The de Broglie wavelength of the incident beam was about 2.5 pm, whereas the diameter of the molecule is about 1 nm, about 400 times larger. In 2012, these far-field diffraction experiments could be extended to phthalocyanine molecules and their heavier derivatives, which are composed of 58 and 114 atoms respectively. In these experiments the build-up of such interference patterns could be recorded in real time and with single molecule sensitivity.[14]

In 2003, the Vienna group also demonstrated the wave nature of tetraphenylporphyrin[15]—a flat biodye with an extension of about 2 nm and a mass of 614 u. For this demonstration they employed a near-field Talbot Lau interferometer.[16][17] In the same interferometer they also found interference fringes for C60F48, a fluorinated buckyball with a mass of about 1600 u, composed of 108 atoms.[15] Large molecules are already so complex that they give experimental access to some aspects of the quantum-classical interface, i.e., to certain decoherence mechanisms.[18][19] In 2011, the interference of molecules as heavy as 6910 u could be demonstrated in a Kapitza–Dirac–Talbot–Lau interferometer.[20] In 2013, the interference of molecules beyond 10,000 u has been demonstrated.[21]

The 2008 comprehensive review by Alexander D. Cronin, Jörg Schmiedmayer, and David E. Pritchard documents many new experimental approaches to atom interferometry.[22] More recently atom interferometers have begun moving out of laboratory conditions and have begun to address a variety of applications in real world environments.[23][24]

Applications

Gravitational physics

A precise measurement of gravitational redshift was made in 2009 by Holger Muller, Achim Peters, and Steven Chu. No violations of general relativity were found to 7 × 10-9.[25]

In 2020, Peter Asenbaum, Chris Overstreet, Minjeong Kim, Joseph Curti, and Mark A. Kasevich used atom interferometry to test the principle of equivalence in general relativity. They found no violations to about 10-12.[26][27]

Inertial navigation

The first team to make a working model, Pritchard's, was propelled by David Keith.[28] Atomic interferometer gyroscopes (AIG) and atomic spin gyroscopes (ASG) use atomic interferometer to sense rotation or in the latter case, uses atomic spin to sense rotation with both having compact size, high precision, and the possibility of being made on a chip-scale.[29][30] "AI gyros" may compete, along with ASGs, with the established ring laser gyroscope, fiber optic gyroscope and hemispherical resonator gyroscope in future inertial guidance applications.[31]

See also

References

  1. ↑ Hecht, Eugene (2017). Optics (5th ed.). Pearson. ISBN 978-0-133-97722-6. 
  2. ↑ Dimopoulos, S. (2009). "Gravitational wave detection with atom interferometry". Physics Letters B 678 (1): 37–40. doi:10.1016/j.physletb.2009.06.011. Bibcode: 2009PhLB..678...37D. 
  3. ↑ Stray, Ben; Lamb, Andrew; Kaushik, Aisha; Vovrosh, Jamie; Winch, Jonathan; Hayati, Farzad; Boddice, Daniel; Stabrawa, Artur et al. (2020). "Quantum sensing for gravity cartography". Nature 602 (7898): 590–594. doi:10.1038/s41586-021-04315-3. PMID 35197616. 
  4. ↑ Cronin, A. D.; Schmiedmayer, J.; Pritchard, D. E. (2009). "Optics and interferometry with atoms and molecules". Rev. Mod. Phys. 81 (3): 1051–1129. doi:10.1103/RevModPhys.81.1051. Bibcode: 2009RvMP...81.1051C. 
  5. ↑ Adams, C. S.; Sigel, M.; Mlynek, J. (1994). "Atom Optics". Phys. Rep. 240 (3): 143–210. doi:10.1016/0370-1573(94)90066-3. Bibcode: 1994PhR...240..143A. 
  6. ↑ Hornberger, K. (2012). "Colloquium: Quantum interference of clusters and molecules". Rev. Mod. Phys. 84 (1): 157. doi:10.1103/revmodphys.84.157. Bibcode: 2012RvMP...84..157H. 
  7. ↑ Rasel, E. M. (1995). "Atom Wave Interferometry with Diffraction Gratings of Light". Phys. Rev. Lett. 75 (14): 2633–2637. doi:10.1103/physrevlett.75.2633. PMID 10059366. Bibcode: 1995PhRvL..75.2633R. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1006&context=physicsbatelaan. 
  8. ↑ Estermann, I.; Stern, Otto (1930). "Beugung von Molekularstrahlen". Z. Phys. 61 (1–2): 95. doi:10.1007/bf01340293. Bibcode: 1930ZPhy...61...95E. 
  9. ↑ Carnal, O.; Mlynek, J. (1991). "Young's double-slit experiment with atoms: A simple atom interferometer". Phys. Rev. Lett. 66 (21): 2689–2692. doi:10.1103/physrevlett.66.2689. PMID 10043591. Bibcode: 1991PhRvL..66.2689C. http://elib.bsu.by/handle/123456789/154548. 
  10. ↑ Keith, D.W.; Ekstrom, C.R.; Turchette, Q.A.; Pritchard, D.E. (1991). "An interferometer for atoms". Phys. Rev. Lett. 66 (21): 2693–2696. doi:10.1103/physrevlett.66.2693. PMID 10043592. Bibcode: 1991PhRvL..66.2693K. 
  11. ↑ Riehle, F.; Th; Witte, A.; Helmcke, J.; Ch; Bordé, J. (1991). "Optical Ramsey spectroscopy in a rotating frame: Sagnac effect in a matter-wave interferometer". Phys. Rev. Lett. 67 (2): 177–180. doi:10.1103/physrevlett.67.177. PMID 10044514. Bibcode: 1991PhRvL..67..177R. 
  12. ↑ Kasevich, M.; Chu, S. (1991). "Atomic interferometry using stimulated Raman transitions". Phys. Rev. Lett. 67 (2): 181–184. doi:10.1103/physrevlett.67.181. PMID 10044515. Bibcode: 1991PhRvL..67..181K. 
  13. ↑ Arndt, Markus; O. Nairz; J. Voss-Andreae, C. Keller, G. van der Zouw, A. Zeilinger (14 October 1999). "Wave–particle duality of C60". Nature 401 (6754): 680–682. doi:10.1038/44348. PMID 18494170. Bibcode: 1999Natur.401..680A. 
  14. ↑ Juffmann, Thomas (25 March 2012). "Real-time single-molecule imaging of quantum interference". Nature Nanotechnology 7 (5): 297–300. doi:10.1038/nnano.2012.34. PMID 22447163. Bibcode: 2012NatNa...7..297J. 
  15. ↑ 15.0 15.1 Hackermüller, Lucia; Stefan Uttenthaler; Klaus Hornberger; Elisabeth Reiger; Björn Brezger; Anton Zeilinger; Markus Arndt (2003). "The wave nature of biomolecules and fluorofullerenes". Phys. Rev. Lett. 91 (9): 090408. doi:10.1103/PhysRevLett.91.090408. PMID 14525169. Bibcode: 2003PhRvL..91i0408H. 
  16. ↑ Clauser, John F.; S. Li (1994). "Talbot von Lau interefometry with cold slow potassium atoms.". Phys. Rev. A 49 (4): R2213–2217. doi:10.1103/PhysRevA.49.R2213. PMID 9910609. Bibcode: 1994PhRvA..49.2213C. 
  17. ↑ Brezger, Björn; Lucia Hackermüller; Stefan Uttenthaler; Julia Petschinka; Markus Arndt; Anton Zeilinger (2002). "Matter-wave interferometer for large molecules". Phys. Rev. Lett. 88 (10): 100404. doi:10.1103/PhysRevLett.88.100404. PMID 11909334. Bibcode: 2002PhRvL..88j0404B. 
  18. ↑ Hornberger, Klaus; Stefan Uttenthaler; Björn Brezger; Lucia Hackermüller; Markus Arndt; Anton Zeilinger (2003). "Observation of Collisional Decoherence in Interferometry". Phys. Rev. Lett. 90 (16): 160401. doi:10.1103/PhysRevLett.90.160401. PMID 12731960. Bibcode: 2003PhRvL..90p0401H. 
  19. ↑ Hackermüller, Lucia; Klaus Hornberger; Björn Brezger; Anton Zeilinger; Markus Arndt (2004). "Decoherence of matter waves by thermal emission of radiation". Nature 427 (6976): 711–714. doi:10.1038/nature02276. PMID 14973478. Bibcode: 2004Natur.427..711H. 
  20. ↑ Gerlich, Stefan (2011). "Quantum interference of large organic molecules". Nature Communications 2 (263): 263. doi:10.1038/ncomms1263. PMID 21468015. Bibcode: 2011NatCo...2..263G. 
  21. ↑ Eibenberger, S.; Gerlich, S.; Arndt, M.; Mayor, M.; Tüxen, J. (2013). "Matter–wave interference of particles selected from a molecular library with masses exceeding 10 000 amu". Physical Chemistry Chemical Physics 15 (35): 14696–14700. doi:10.1039/c3cp51500a. PMID 23900710. Bibcode: 2013PCCP...1514696E. 
  22. ↑ Cronin, Alexander D.; Schmiedmayer, Jörg; Pritchard, David E. (2009). "Optics and interferometry with atoms and molecules". Reviews of Modern Physics 81 (3): 1051–1129. doi:10.1103/RevModPhys.81.1051. Bibcode: 2009RvMP...81.1051C. 
  23. ↑ Bongs, K.; Holynski, M.; Vovrosh, J.; Bouyer, P.; Condon, G.; Rasel, E.; Schubert, C.; Schleich, W.P. et al. (2019). "Taking atom interferometric quantum sensors from the laboratory to real-world applications". Nat. Rev. Phys. 1 (12): 731–739. doi:10.1038/s42254-019-0117-4. Bibcode: 2019NatRP...1..731B. 
  24. ↑ Vovrosh, J.; Dragomir, A.; Stray, B.; Boddice, B. (2023). "Advances in Portable Atom Interferometry-Based Gravity Sensing". Sensors 23 (7): 7651. doi:10.3390/s23177651. PMID 37688106. Bibcode: 2023Senso..23.7651V. 
  25. ↑ Muller, Holger; Peters, Achim; Chu, Steven (2010). "A precision measurement of the gravitational redshift by the interference of matter waves". Nature 463 (7283): 926–929. doi:10.1038/nature08776. PMID 20164925. Bibcode: 2010Natur.463..926M. https://www.nature.com/articles/nature08776. 
  26. ↑ Asenbaum, Peter; Overstreet, Chris; Kim, Minjeong; Curti, Joseph; Kasevich, Mark A. (2020). "Atom-Interferometric Test of the Equivalence Principle at the 10−12 Level". Physical Review Letters 125 (19): 191101. doi:10.1103/PhysRevLett.125.191101. PMID 33216577. https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.191101. 
  27. ↑ Conover, Emily (October 28, 2020). "Galileo's famous gravity experiment holds up, even with individual atoms". Science News. https://www.sciencenews.org/article/galileo-gravity-experiment-atoms-general-relativity-einstein. 
  28. ↑ Rotman, David (February 8, 2013). "A Cheap and Easy Plan to Stop Global Warming". MIT Technology Review. https://www.technologyreview.com/2013/02/08/84239/a-cheap-and-easy-plan-to-stop-global-warming/. Retrieved 1 July 2021. 
  29. ↑ Fang, Jiancheng; Qin, Jie (2012). "Advances in Atomic Gyroscopes: A View from Inertial Navigation Applications". Sensors 12 (5): 6331–6346. doi:10.3390/s120506331. PMID 22778644. Bibcode: 2012Senso..12.6331F. 
  30. ↑ Advances in Atomic Gyroscopes: A View from Inertial Navigation Applications. Full PDF
  31. ↑ Cold Atom Gyros – IEEE Sensors 2013

External links

  • P. R. Berman [Editor], Atom Interferometry. Academic Press (1997). Detailed overview of atom interferometers at that time (good introductions and theory).
  • Stedman Review of the Sagnac Effect



Retrieved from "https://handwiki.org/wiki/index.php?title=Physics:Atom_interferometer&oldid=3283005"