Strong coupling treatment of the polaronic system consisting of an impurity in a condensate

Laser Physics - Tập 21 - Trang 1480-1485 - 2011
W. Casteels1, T. Van Cauteren1, J. Tempere1,2, J. T. Devreese1
1TQC, Universiteit Antwerpen, Antwerpen, Belgium
2Lyman Laboratory of Physics, Harvard University, Cambridge, USA

Tóm tắt

The strong coupling treatment of the Fröhlich-type polaronic system, based on a canonical transformation and a standard Landau-Pekar type variational wave function, is applied to the polaronic system consisting of an impurity in a condensate. Within this approach the Relaxed Excited States are retrieved as a typical polaronic feature in the energy spectrum. For these states we calculate the corresponding effective mass and the minimal coupling constant required for them to occur. The present approach allows to derive approximate expressions for the transition energies between different Relaxed Excited States in a much simpler way than with the full Mori-Zwanzig approach, and with a good accuracy, which improves with increasing coupling. The transition energies obtained here can be used as the spectroscopic fingerprint for the experimental observation of Relaxed Excited States of impurities in a condensate.

Tài liệu tham khảo

I. Bloch, J. Dalibard, and W. Zwerger, Rev. Mod. Phys. 80, 885 (2008).

V. Nesterenko, A. Novikov, F. de Souza Cruz, and E. Lapolli, Laser Phys. 19, 616 (2009).

V. Nesterenko, A. Novikov, and E. Suraud, Laser Phys. 20, 1149 (2010).

F. M. Cucchietti and E. Timmermans, Phys. Rev. Lett. 96, 210401 (2006).

K. Sacha and E. Timmermans, Phys. Rev. A 73, 063604 (2006).

M. Bruderer, A. Klein, S. R. Clark, and D. Jaksch, New J. Phys. 10, 033015 (2008).

M. Bruderer, A. Klein, S. R. Clark, R. Stephen, and D. Jaksch, Phys. Rev. A 76, 011605 (2007).

A. Privitera and W. Hofstetter, Phys. Rev. A 82, 063614 (2010).

J. T. Devreese, Polarons, arXiv:cond-mat/0004497v2.

J. T. Devreese and A. S. Alexandrov, Advances in Polaron Physics (Springer, Berlin, 2010).

R. P. Feynman, Phys. Rev. 97, 660 (1955).

E. Kartheuser, R. Evrard, and J. Devreese, Phys. Rev. Lett. 22, 94 (1969).

J. Devreese, J. de Sitter, and M. Goovaerts, Phys. Rev. B 5, 2367 (1972).

A. S. Mishchenko, N. Nagaosa, N. V. Prokof’ev, A. Sakamoto, and B. V. Svistunov, Phys. Rev. Lett. 91, 236401 (2003).

G. De Filippis, V. Cataudella, A. S. Mishchenko, C. A. Perroni, and J. T. Devreese, Phys. Rev. Lett. 96, 136405 (2006).

A. S. Alexandrov, Polarons in Advanced Materials (Springer, Berlin, 2007), pp. 257–310, and references therein.

W. Casteels, J. Tempere, and J. T. Devreese, Phys. Rev. A 83, 033631 (2011).

J. Tempere, W. Casteels, M. K. Oberthaler, S. Knoop, E. Timmermans, and J. T. Devreese, Phys. Rev. B 80, 184504 (2009).

L. Pitaevskii and S. Stringari, Bose-Einstein Condensation (Oxford Univ., Oxford, 2003).

L. D. Landau and S. I. Pekar, Zh. Eksp. Teor. Fiz. 16, 341 (1946); Zh. Eksp. Teor. Fiz. 18, 419 (1948).

J. Devreese and R. Evrard, Phys. Lett. 23, 196 (1966).

S. I. Pekar, Untersuchungen über die elektronentheorie der Kristalle (Akademic Verlag, Berlin, 1951) [in German].

N. N. Bogoliubov, Ukr. Matem. Zh. 2, 3 (1950); in Advanced in Theoretical Physics, Ed. by E. Caianiello (World Sci., Singapore, 1991), pp. 1–18.

P. Vansant, M. A. Smondyrev, F. M. Peelers, and J. T. Devreese, J. Phys. A: Math. Gen. 27, 7925 (1994).

R. Evrard, Phys. Lett. 14, 295 (1965).

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Thông tin xuất bản

Laser Physics

Tập 21

1480-1485

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