1108.0425 (Nabil Iqbal et al.)

Quantum phase transitions in semi-local quantum liquids    [PDF]

Nabil Iqbal, Hong Liu, Márk Mezei

We consider several types of quantum critical phenomena from finite-density
gauge-gravity duality which to different degrees lie outside the
Landau-Ginsburg-Wilson paradigm. These include: (1) a "bifurcating" critical
point, for which the order parameter remains gapped at the critical point, and
thus is not driven by soft order parameter fluctuations. Rather it appears to
be driven by "confinement" which arises when two fixed points annihilate and
lose conformality. On the condensed side, there is an infinite tower of
condensed states and the nonlinear response of the tower exhibits an infinite
spiral structure; (2) a "hybridized" critical point which can be described by a
standard Landau-Ginsburg sector of order parameter fluctuations hybridized with
a strongly coupled sector; (3) a "marginal" critical point which is obtained by
tuning the above two critical points to occur together and whose bosonic
fluctuation spectrum coincides with that postulated to underly the "Marginal
Fermi Liquid" description of the optimally doped cuprates.

View original: http://arxiv.org/abs/1108.0425