Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping

Details Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping

2004-10-06

arxiv.org/abs/cond-mat/0410132v4

Phys. Rev. Lett. 94, 070604 (2005)

Physics

Condensed Matter

Statistical Mechanics

4 pages, 3 figs; (v2) discussion extended; (v3) marginal changes, final version as published; (v4) added erratum pointing out

Scientific paper

10.1103/PhysRevLett.94.070604

The effective theories for many quantum phase transitions can be mapped onto those of classical transitions. Here we show that such a mapping fails for the sub-ohmic spin-boson model which describes a two-level system coupled to a bosonic bath with power-law spectral density, J(omega) ~ omega^s. Using an epsilon expansion we prove that this model has a quantum transition controlled by an interacting fixed point at small s, and support this by numerical calculations. In contrast, the corresponding classical long-range Ising model is known to have an upper-critical dimension at s = 1/2, with mean-field transition behavior controlled by a non-interacting fixed point for 0 < s < 1/2. The failure of the quantum-classical mapping is argued to arise from the long-ranged interaction in imaginary time in the quantum model.

Affiliated with

Also associated with

No associations

Rating

Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-169609