Anomalous scaling at the quantum critical point in itinerant antiferromagnets. Academic Article uri icon

abstract

  • We show that the Hertz phi(4) theory of quantum criticality is incomplete as it misses anomalous nonlocal contributions to the interaction vertices. For antiferromagnetic quantum transitions, we found that the theory is renormalizable only if the dynamical exponent z=2. The upper critical dimension is still d=4 - z=2; however, the number of marginal vertices at d=2 is infinite. As a result, the theory has a finite anomalous exponent already at the upper critical dimension. We show that for d<2 the Gaussian fixed point splits into two non-Gaussian fixed points. For both fixed points, the dynamical exponent remains z=2.

published proceedings

  • Phys Rev Lett

author list (cited authors)

  • Abanov, A. r., & Chubukov, A.

citation count

  • 116

complete list of authors

  • Abanov, Ar||Chubukov, A

publication date

  • December 2004