A. Abanov et Av. Chubukov, Spin-fermion model near the quantum critical point: One-loop renormalization group results, PHYS REV L, 84(24), 2000, pp. 5608-5611
We consider spin and electronic properties of itinerant electron systems, d
escribed by the spin-fermion model, near the antiferromagnetic critical poi
nt. We expand in the inverse number of hot spots in the Brillouin zone, N,
and present the results beyond the previously studied N = infinity limit. W
e found two new effects: (i) Fermi surface becomes nested at hot spots, and
(ii) vertex corrections give rise to anomalous spin dynamics and change th
e dynamical critical exponent From z = 2 to z > 2. To first order in 1/N we
found z = 2N/(N - 2) which for a physical N = 8 yields z approximate to 2.
67.