Gapless spinfluid ground state in a random quantum Heisenberg magnet
Abstract
We examine the spinS quantum Heisenberg magnet with Gaussianrandom, infiniterange exchange interactions. The quantumdisordered phase is accessed by generalizing to SU(M) symmetry and studying the large M limit. For large S the ground state is a spin glass, while quantum fluctuations produce a spinfluid state for small S. The spinfluid phase is found to be generically gaplessthe average, zero temperature, local dynamic spin susceptibility obeys χ̄(ω)~ln(1/ω)+i(π/2)sgn(ω) at low frequencies.
 Publication:

Physical Review Letters
 Pub Date:
 May 1993
 DOI:
 10.1103/PhysRevLett.70.3339
 arXiv:
 arXiv:condmat/9212030
 Bibcode:
 1993PhRvL..70.3339S
 Keywords:

 75.10.Jm;
 05.30.d;
 75.50.Ee;
 Quantized spin models;
 Quantum statistical mechanics;
 Antiferromagnetics;
 Condensed Matter
 EPrint:
 13 pages, REVTEX, 2 figures available by request from subir@cmphys.eng.yale.edu