Acoustic dispersion in a two-dimensional dipole system

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Kenneth I. Golden
Department of Mathematics and Statistics, College of Engineering and Mathematical Sciences, University of Vermont, Burlington, Vermont 05401-1455, USA

Gabor J. Kalman
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, USA

Zoltan Donko and Peter Hartmann
Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary

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Received 3 April 2008; published 8 July 2008

Wecalculate the full density response function and from it thelong-wavelength acoustic dispersion for a two-dimensional system of strongly coupledpoint dipoles interacting through a 1/r³ potential at arbitrary degeneracy.Such a system has no random-phase-approximation (RPA) limit and thecalculation has to include correlations from the outset. We followthe quasilocalized charge (QLC) approach, accompanied by molecular-dynamics (MD) simulations.Similarly to what has been recently reported for the closelyspaced classical electron-hole bilayer [G. J. Kalman et al., Phys. Rev.Lett. 98, 236801 (2007)] and in marked contrast to theRPA, we report a long-wavelength acoustic phase velocity that iswholly maintained by particle correlations and varies linearly with thedipole moment p. The oscillation frequency, calculated both in anextended QLC approximation and in the Singwi-Tosi-Land-Sjolander approximation [Phys. Rev.176, 589 (1968)], is invariant in form over the entireclassical to quantum domains all the way down to zerotemperature. Based on our classical MD-generated pair distribution function dataand on ground-state energy data generated by recent quantum MonteCarlo simulations on a bosonic dipole system [G. E. Astrakharchiket al., Phys. Rev. Lett. 98, 060405 (2007)], there is agood agreement between the QLC approximation kinetic sound speeds andthe standard thermodynamic sound speeds in both the classical andquantum domains.

URL:	http://link.aps.org/doi/10.1103/PhysRevB.78.045304
DOI:	10.1103/PhysRevB.78.045304
PACS:	71.35.Ee; 52.27.Gr; 52.65.Yy; 05.30.Jp 71.35.Ee Electron-hole drops and electron-hole plasma 52.27.Gr Strongly-coupled plasmas 52.65.Yy Molecular dynamics methods (plasma simulation) 05.30.Jp Boson systems (quantum statistical mechanics) YEAR: 2008
KEYWORDS:	acoustic wave effects, acoustic wave velocity, ground states, molecular dynamics method

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Yu. E. Lozovik and O. L. Berman, JETP 84, 1027 (1997)
Phys. Solid State 40, 1228 (1998)
S. De Palo, F. Rapisarda, and G. Senatore, Phys. Rev. Lett. 88, 206401 (2002).
(b) S. Ranganathan and R. E. Johnson, Phys. Rev. B 75, 155314 (2007).
Y. N. Joglekar, A. V. Balatsky, and S. Das Sarma, Phys. Rev. B 74, 233302 (2006).
[JETP Lett. 22, 274 (1975)]
T. Fukuzawa, E. E. Mendez, and J. M. Hong, Phys. Rev. Lett. 64, 3066 (1990).
(a) G. E. Astrakharchik, J. Boronat, I. L. Kurbakov, and Yu. E. Lozovik, Phys. Rev. Lett. 98, 060405 (2007)
D. M. Kachintsev and S. E. Ulloa, Phys. Rev. B 50, 8715 (1994).
H. P. Büchler, E. Demler, M. Lukin, A. Micheli, N. Prokof'ev, G. Pupillo, and P. Zoller, Phys. Rev. Lett. 98, 060404 (2007).
G. J. Kalman, P. Hartmann, Z. Donko, and K. I. Golden, Phys. Rev. Lett. 98, 236801 (2007).
G. Kalman and K. I. Golden, Phys. Rev. A 41, 5516 (1990)

Phys. Plasmas 7, 14 (2000)

ibid. 8, 5064 (2001)

K. S. Singwi, M. P. Tosi, R. H. Land, and A. Sjölander, Phys. Rev. 176, 589 (1968)
R. K. Moudgil, P. K. Ahluwalia, and K. N. Pathak, Phys. Rev. B 52, 11945 (1995).
K. I. Golden, H. Mahassen, and G. J. Kalman, Phys. Rev. E 70, 026406 (2004).
J. C. Kimball, Phys. Rev. A 7, 1648 (1973).
Y. Yafet, J. Kwo, and E. M. Gyorgy, Phys. Rev. B 33, 6519 (1986).
R. P. Erickson, Phys. Rev. B 46, 14194 (1992).
V. M. Rozenbaum, Phys. Rev. B 53, 6240 (1996).