Europhys. Lett.
Volume 62, Number 6, June 2003
Page(s) 890 - 896
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 June 2003
DOI: 10.1209/epl/i2003-00456-2
Europhys. Lett., 62 (6) , pp. 890-896 (2003)

Metallic continuum quantum ferromagnets at finite temperature

M. B. Silva Neto and A. H. Castro Neto

Department of Physics, Boston University - Boston, MA 02215, USA

(Received 13 March 2003; accepted 14 April 2003)

We study via renormalization group (RG) and large N methods the problem of continuum SU(N) quantum Heisenberg ferromagnets (QHF) coupled to gapless electrons. We establish the phase diagram of the dissipative problem and investigate the changes in the Curie temperature, magnetization, and magnetic correlation length due to dissipation and both thermal and quantum fluctuations. We show that the interplay between the topological term (Berry's phase) and dissipation leads to non-trivial effects for the finite temperature critical behavior.

75.10.Jm - Quantized spin models.
75.40.Gb - Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.).

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