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Layers of cold dipolar molecules in the harmonic approximation

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Abstract

We consider the N-body problem in a layered geometry containing cold polar molecules with dipole moments that are polarized perpendicular to the layers. A harmonic approximation is used to simplify the Hamiltonian and bound state properties of the two-body inter-layer dipolar potential are used to adjust this effective interaction. To model the intra-layer repulsion of the polar molecules, we introduce a repulsive inter-molecule harmonic potential and discuss how its strength can be related to the real dipolar potential. However, to explore different structures with more than one molecule in each layer, we treat the repulsive harmonic strength as an independent variable in the problem. Single chains containing one molecule in each layer, as well as multi-chain structures in many layers are discussed and their energies and radii determined. We extract the normal modes of the various systems as measures of their volatility and eventually of instability, and compare our findings to the excitations in crystals. We find modes that can be classified as either chains vibrating in phase or as layers vibrating against each other. The former correspond to acoustic and the latter to optical phonons. For the acoustic modes, our model predicts a smaller sound speed than one would naively get from expansion of the dipolar potential to second order around the origin. Instabilities can occur for large intra-layer repulsion and produce diverging amplitudes of molecules in the outer layers, and our model predicts how the breakup takes places. Lastly, we consider experimentally relevant regimes to observe the structures. The harmonic model considered here predicts that for the multi-layer systems under current study chains with one molecule in each layer are always bound whereas two chains comprised of two molecules in each layer will not be bound. However, since realistic systems have external confinement prevention the molecules from escaping to infinity, we still expect the unstable modes to show up as resonances in the dynamics.

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References

  1. S. Ospelkaus et al., Nat. Phys. 4, 622 (2008)

    Article  Google Scholar 

  2. K.-K. Ni et al., Science 322, 231 (2008)

    Article  ADS  Google Scholar 

  3. J. Deiglmayr et al., Phys. Rev. Lett. 101, 133004 (2008)

    Article  ADS  Google Scholar 

  4. F. Lang et al., Phys. Rev. Lett. 101, 133005 (2008)

    Article  ADS  Google Scholar 

  5. D. Wang et al., Phys. Rev. A 81, 061404(R) (2010)

    ADS  Google Scholar 

  6. B.C. Sawyer et al., Phys. Chem. Chem. Phys. 13, 19059 (2011)

    Article  Google Scholar 

  7. K.-K. Ni et al., Nature 464, 1324 (2010)

    Article  ADS  Google Scholar 

  8. S. Ospelkaus et al., Science 327, 853 (2010)

    Article  ADS  Google Scholar 

  9. L.D. Carr, D. DeMille, R.V. Krems, J. Ye, New J. Phys. 11, 055049 (2009)

    Article  ADS  Google Scholar 

  10. M.G.H. de Miranda et al., Nat. Phys. 7, 502 (2011)

    Article  Google Scholar 

  11. M.A. Baranov, Phys. Rep. 464, 71 (2008)

    Article  ADS  Google Scholar 

  12. T. Lahaye, C. Menotti, L. Santos, M. Lewenstein, T. Pfau, Rep. Prog. Phys. 72, 126401 (2009)

    Article  ADS  Google Scholar 

  13. K. Góral, L. Santos, M. Lewenstein, Phys. Rev. Lett. 88, 170406 (2002)

    Article  Google Scholar 

  14. D. DeMille, Phys. Rev. Lett. 88, 069701 (2002)

    Article  Google Scholar 

  15. R. Barnett, D. Petrov, M. Lukin, E. Demler, Phys. Rev. Lett. 96, 190401 (2006)

    Article  ADS  Google Scholar 

  16. A. Micheli, G.K. Brennen, P. Zoller, Nat. Phys. 2, 341 (2006)

    Article  Google Scholar 

  17. D.-W. Wang, M.D. Lukin, E. Demler, Phys. Rev. Lett. 97, 180413 (2006)

    Article  ADS  Google Scholar 

  18. P.M. Lushnikov, Phys. Rev. A 66, 051601 (2002)

    Article  MathSciNet  ADS  Google Scholar 

  19. A. Micheli, Z. Idziaszek, G. Pupillo, M.A. Baranov, P. Zoller, P.S. Julienne, Phys. Rev. Lett. 105, 073202 (2010)

    Article  ADS  Google Scholar 

  20. S.-M. Shih, D.-W. Wang, Phys. Rev. A 79, 065603 (2009)

    Article  ADS  Google Scholar 

  21. D.V. Fedorov, J.R. Armstrong, N.T. Zinner, A.S. Jensen, Few-Body Syst. 50, 417 (2011)

    Article  ADS  Google Scholar 

  22. M. Klawunn, A. Pikovski, L. Santos, Phys. Rev. A 82, 044701 (2010)

    Article  ADS  Google Scholar 

  23. B. Wunsch, N.T. Zinner, I.B. Mekhov, S.J. Huang, D.-W. Wang, E. Demler, Phys. Rev. Lett. 107, 073201 (2011)

    Article  ADS  Google Scholar 

  24. N.T. Zinner, B. Wunsch, I.B. Mekhov, S.J. Huang, D.-W. Wang, E. Demler, Phys. Rev. A 84, 063606 (2011)

    Article  ADS  Google Scholar 

  25. J.C. Cremon, G.M. Bruun, S.M. Reimann, Phys. Rev. Lett. 105, 255301 (2010)

    Article  ADS  Google Scholar 

  26. J.R. Armstrong, N.T. Zinner, D.V. Fedorov, A.S. Jensen, Europhys. Lett. 91, 16001 (2010)

    Article  ADS  Google Scholar 

  27. A.G. Volosniev, D.V. Fedorov, A.S. Jensen, N.T. Zinner, Phys. Rev. Lett. 106, 250401 (2011)

    Article  ADS  Google Scholar 

  28. A.G. Volosniev, N.T. Zinner, D.V. Fedorov, A.S. Jensen, B. Wunsch, J. Phys. B 44, 125301 (2011)

    Article  ADS  Google Scholar 

  29. N.T. Zinner, J.R. Armstrong, A.G. Volosniev, D.V. Fedorov, A.S. Jensen, Few-Body Syst. (2012), online first

  30. G.M. Bruun, E. Taylor, Phys. Rev. Lett. 101, 245301 (2008)

    Article  ADS  Google Scholar 

  31. R.M. Lutchyn, E. Rossi, S. Das Sarma, Phys. Rev. A 82, 061604(R) (2009)

    ADS  Google Scholar 

  32. N.R. Cooper, G.V. Shlyapnikov, Phys. Rev. Lett. 103, 155302 (2009)

    Article  ADS  Google Scholar 

  33. K. Sun, C. Wu, S. Das Sarma, Phys. Rev. B 82, 075105 (2010)

    Article  ADS  Google Scholar 

  34. Y. Yamaguchi, T. Sogo, T. Ito, T. Miyakawa, Phys. Rev. A 82, 013643 (2010)

    Article  ADS  Google Scholar 

  35. A. Pikovski, M. Klawunn, G.V. Shlyapnikov, L. Santos, Phys. Rev. Lett. 105, 215302 (2010)

    Article  ADS  Google Scholar 

  36. F. Herrera, M. Litinskaya, R.V. Krems, Phys. Rev. A 82, 033428 (2010)

    Article  ADS  Google Scholar 

  37. L. Pollet, J.D. Picon, H.P. Büchler, M. Troyer, Phys. Rev. Lett. 104, 125302 (2010)

    Article  ADS  Google Scholar 

  38. N.T. Zinner, B. Wunsch, D. Pekker, D.-W. Wang, Phys. Rev. A 85, 013603 (2012)

    Article  ADS  Google Scholar 

  39. N.T. Zinner, G.M. Bruun, Eur. Phys. J. D 65, 133 (2011)

    Article  ADS  Google Scholar 

  40. J. Levinsen, N.R. Cooper, G.V. Shlyapnikov, Phys. Rev. A 84, 013603 (2011)

    Article  ADS  Google Scholar 

  41. L. He, W. Hofstetter, Phys. Rev. A 83, 053629 (2011)

    Article  ADS  Google Scholar 

  42. E. Wigner, Phys. Rev. 46, 1002 (1934)

    Article  ADS  MATH  Google Scholar 

  43. L. Bonsall, A.A. Maradudin, Phys. Rev. B 15, 1959 (1977)

    Article  ADS  Google Scholar 

  44. R.K. Kalia, P. Vashishta, J. Phys. C 14, L643 (1981)

    Article  ADS  Google Scholar 

  45. V.M. Bedanov, G.V. Gadiyak, Yu.E. Lozovik, JETP Lett. 61, 967 (1985)

    Google Scholar 

  46. C. Mora, O. Parcollet, X. Waintal, Phys. Rev. B 76, 064511 (2007)

    Article  ADS  Google Scholar 

  47. H.P. Büchler et al., Phys. Rev. Lett. 98, 060404 (2007)

    Article  Google Scholar 

  48. G.E. Astrakharchik, J. Boronat, I.L. Kurbakov, Yu.E. Lozovik, Phys. Rev. Lett. 98, 060405 (2007)

    Article  ADS  Google Scholar 

  49. A.S. Arkhipov, G.E. Astrakharchik, A.V. Belikov, Yu. E. Lozovik, JETP Lett. 82, 39 (2005)

    Article  ADS  Google Scholar 

  50. P. Rabl, P. Zoller, Phys. Rev. A 76, 042308 (2007)

    Article  ADS  Google Scholar 

  51. C. Menotti, C. Trefzger, M. Lewenstein, Phys. Rev. Lett. 98, 235301 (2007)

    Article  ADS  Google Scholar 

  52. C. Kollath, J.S. Meyer, T. Giamarchi, Phys. Rev. Lett. 100, 130403 (2008)

    Article  ADS  Google Scholar 

  53. R. Citro, E. Orignac, S. De Palo, M.L. Chiofalo, Phys. Rev. A 75, 051602 (2007)

    Article  ADS  Google Scholar 

  54. G.E. Astrakharchik, G. Morigi, G. De Chiara, J. Boronat, Phys. Rev. A 78, 063622 (2008)

    Article  ADS  Google Scholar 

  55. Y.-P. Huang, D.-W. Wang, Phys. Rev. A 80, 053610 (2009)

    Article  ADS  Google Scholar 

  56. C.-M. Chang, W.-C. Shen, C.-Y. Lai, P. Chen, D.-W. Wang, Phys. Rev. A 79, 053630 (2009)

    Article  ADS  Google Scholar 

  57. S. Fishman, G. De Chiara, T. Calarco, G. Morigi, Phys. Rev. B 77, 064111 (2008)

    Article  ADS  Google Scholar 

  58. P.F. Herskind, A. Dantan, J. Marler, M. Albert, M. Drewsen, Nat. Phys. 5, 494 (2009)

    Article  Google Scholar 

  59. J. Quintanilla, S.T. Carr, J.J. Betouras, Phys. Rev. A 79, 031601(R) (2009)

    Article  ADS  Google Scholar 

  60. S.T. Carr, J. Quintanilla, J.J. Betouras, Phys. Rev. B 82, 045110 (2010)

    Article  ADS  Google Scholar 

  61. K.-Y. Zhu, L. Tan, X. Gao, D.-W. Wang, Chin. Phys. Lett. 25, 48 (2008)

    Article  ADS  Google Scholar 

  62. M. Klawunn, J. Duhme, L. Santos, Phys. Rev. A 81, 013604 (2010)

    Article  ADS  Google Scholar 

  63. X. Lu, C.-Q. Wu, A. Micheli, G. Pupillo, Phys. Rev. B 78, 024108 (2008)

    Article  ADS  Google Scholar 

  64. B. Capogrosso-Sansone, A. Kuklov, J. Low Temp. Phys. 165, 213 (2011)

    Article  ADS  Google Scholar 

  65. J.R. Armstrong, N.T. Zinner, D.V. Fedorov, A.S. Jensen, J. Phys. B 44, 055303 (2011)

    Article  ADS  Google Scholar 

  66. A.S. Jensen, K. Riisager, D.V. Fedorov, E. Garrido, Rev. Mod. Phys. 76, 215 (2004)

    Article  ADS  Google Scholar 

  67. A.G. Volosniev, D.V. Fedorov, A.S. Jensen, N.T. Zinner, Phys. Rev. A 85, 023609 (2012)

    Article  ADS  Google Scholar 

  68. N.N. Khuri, A. Martin, T.-T. Wu, Few-Body Syst. 31, 83 (2002)

    Article  ADS  Google Scholar 

  69. S. Giovanazzi, A. Gørlitz, T. Pfau, Phys. Rev. Lett. 89, 130401 (2002)

    Article  ADS  Google Scholar 

  70. A. Micheli, G. Pupillo, H.P. Büchler, P. Zoller, Phys. Rev. A 76, 043604 (2007)

    Article  ADS  Google Scholar 

  71. A.V. Gorshkov, P. Rabl, G. Pupillo, A. Micheli, P. Zoller, M.D. Lukin, H.P. Büchler, Phys. Rev. Lett. 101, 073201 (2008)

    Article  ADS  Google Scholar 

  72. G.E. Astrakharchik, G.B. De Chiara, G. Morigi, J. Boronat, J. Phys. B 42, 154026 (2009)

    Article  ADS  Google Scholar 

  73. P.S. Julienne, T.M. Hanna, Z. Idziaszek, Phys. Chem. Chem. Phys. 13, 19114 (2011)

    Article  Google Scholar 

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Armstrong, J.R., Zinner, N.T., Fedorov, D.V. et al. Layers of cold dipolar molecules in the harmonic approximation. Eur. Phys. J. D 66, 85 (2012). https://doi.org/10.1140/epjd/e2012-20611-x

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