Dissipation effects in random transverse-field Ising chains
arXiv:1203.0698 · doi:10.1103/PhysRevB.85.174403
Abstract
We study the effects of Ohmic, super-Ohmic, and sub-Ohmic dissipation on the zero-temperature quantum phase transition in the random transverse-field Ising chain by means of an (asymptotically exact) analytical strong-disorder renormalization-group approach. We find that Ohmic damping destabilizes the infinite-randomness critical point and the associated quantum Griffiths singularities of the dissipationless system. The quantum dynamics of large magnetic clusters freezes completely which destroys the sharp phase transition by smearing. The effects of sub-Ohmic dissipation are similar and also lead to a smeared transition. In contrast, super-Ohmic damping is an irrelevant perturbation; the critical behavior is thus identical to that of the dissipationless system. We discuss the resulting phase diagrams, the behavior of various observables, and the implications to higher dimensions and experiments.
18 pages, 3 figures; (v2) minor changes, published version
References in corpus (15)
- Fermi-liquid instabilities at magnetic quantum phase transitions
- Rare region effects at classical, quantum, and non-equilibrium phase transitions
- Numerical Renormalization Group for Bosonic Systems and Application to the Subohmic Spin-Boson Model
- Quantum Griffiths effects and smeared phase transitions in metals: theory and experiment
- Phase diagram and critical exponents of a dissipative Ising spin chain in a transverse magnetic field
- Quantum Griffiths effects in itinerant Heisenberg magnets
- Phase transition of one dimensional bosons with strong disorder
- Effects of dissipation on a quantum critical point with disorder
- Infinite-randomness quantum critical points induced by dissipation
- Discovery of Griffiths phase in itinerant magnetic semiconductor Fe_{1-x}Co_xS_2
- Theory of smeared quantum phase transitions
- Finite temperature behavior of strongly disordered quantum magnets coupled to a dissipative bath
- Percolation transition and dissipation in quantum Ising magnets
- Composition-tuned smeared phase transitions
- Influence of superohmic dissipation on a disordered quantum critical point