Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2011-10-28
Phys. Rev. Lett., 108, 160401 (2012)
Physics
Condensed Matter
Statistical Mechanics
Scientific paper
10.1103/PhysRevLett.108.160401
For phase transitions in dissipative quantum impurity models, the existence of a quantum-to-classical correspondence has been discussed extensively. We introduce a variational matrix product state approach involving an optimized boson basis, rendering possible high-accuracy numerical studies across the entire phase diagram. For the sub-ohmic spin-boson model with a power-law bath spectrum $\propto \w^s$, we confirm classical mean-field behavior for $s<1/2$, correcting earlier numerical renormalization-group results. We also provide the first results for an XY-symmetric model of a spin coupled to two competing bosonic baths, where we find a rich phase diagram, including both critical and strong-coupling phases for $s<1$, different from that of classical spin chains. This illustrates that symmetries are decisive for whether or not a quantum-to-classical correspondence exists.
Delft Jan von
Guo Cheng
Vojta Matthias
Weichselbaum Andreas
No associations
LandOfFree
Critical and strong-coupling phases in one- and two-bath spin-boson models 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 Critical and strong-coupling phases in one- and two-bath spin-boson models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Critical and strong-coupling phases in one- and two-bath spin-boson models will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-686146