Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Bulletin of the American Physical Society

Bose-Fermi Kondo model with a local transverse field and its implications for the global phase diagram of heavy fermions

Emilian M. Nica, Qimiao Si A, Kevin Ingersent

Published Mar 20, 2013• 0 citations
OpenAlex

Related papers

Global phase diagram of heavy fermions and the Kondo destroyed quantum critical points of Anderson models with a transverse field

J. H. Pixley, Stefan Kirchner, Qimiao Si A

Bulletin of the American Physical Society•Mar 23, 2011•0 citations

The Ising-Anisotropic Kondo Lattice in a transverse field: EDMFT study and implications for the global phase diagram

Emilian M. Nica, Kevin Ingersent, Qimiao Si A

Bulletin of the American Physical Society•Mar 3, 2015•0 citations

Quantum critical Kondo destruction of the Bose-Fermi Kondo model in the presence of a local transverse field

Emilian M. Nica, Kevin Ingersent, Qimiao Si A

Bulletin of the American Physical Society•Feb 29, 2012•0 citations

The Bose-Fermi Kondo model and heavy-fermion quantum criticality

Matthew T. Glossop, Kevin Ingersent

Bulletin of the American Physical Society•Nov 10, 2005•0 citations

Quantum critical Kondo destruction in the Bose-Fermi Kondo model with a local transverse field

Emilian M. Nica, Kevin Ingersent, Jian‐Xin Zhu +1 more

Recent studies of the global phase diagram of quantum-critical heavy-fermion metals prompt consideration of the interplay between the Kondo interactions and quantum fluctuations of the local moments alone. Toward this goal, we study a Bose-Fermi Kondo model (BFKM) with Ising anisotropy in the presence of a local transverse field that generates quantum fluctuations in the local-moment sector. We apply the numerical renormalization-group method to the case of a sub-Ohmic bosonic bath exponent and a constant conduction-electron density of states. Starting in the Kondo phase at zero transverse field, there is a smooth crossover with increasing transverse field from a fully screened to a fully polarized impurity spin. By contrast, if the system starts in its localized phase, then increasing the transverse field causes a continuous, Kondo-destruction transition into the partially polarized Kondo phase. The critical exponents at this quantum phase transition exhibit hyperscaling and take essentially the same values as those of the BFKM in zero transverse field. The many-body spectrum at criticality varies continuously with the bare transverse field, indicating a line of critical points. We discuss implications of these results for the global phase diagram of the Kondo lattice model.

arXiv:1307.1614•Physical Review B•Jul 15, 2013•5 citations

Kondo destruction Quantum Phase Transition in SU(2) symmetric Bose-Fermi Anderson Model.

Ang Cai, Qimiao Si A

In quantum critical heavy fermion systems, local moments are coupled to both collective spin fluctuations and conduction electrons. As such, the Bose-Fermi Kondo model, describing the coupling of a local moment to both a bosonic and a fermionic bath, has been of extensive interest. For the model in the presence of SU(2) spin rotational symmetry, questions have been raised about its phase diagram. Here we develop a version of continuous-time Quantum Monte Carlo (CT-QMC) method suitable for addressing this issue; this procedure can reach sufficiently low temperatures while preserving the SU(2) symmetry. Using this method for the Bose-Fermi Anderson model, we clarify the renormalization-group fixed points and the phase diagram for the case with a constant fermionic-bath density of states and a power-law bosonic-bath spectral function $\rho_{b}(\omega) \propto \omega^{s}$ ($0<s<1$). We find two types of Kondo destruction QCP, depending on the power-law exponent $s$ in the bosonic bath spectrum. For $s^{*}<s<1$, both types of QCPs exist and, in the parameter regime accessible by an analytical $\epsilon$-expansion renormalization-group calculation (here $\epsilon=1-s$), the CT-QMC result is fully consistent with prior predictions by the latter method. For $s<s^{*}$, there is only one type of QCP. At both type of Kondo destruction QCPs, we find that the exponent of the local spin susceptibility $\eta$ obeys the relation $\eta=\epsilon$, which has important implications for Kondo destruction QCP in the Kondo lattice problem.

•Feb 26, 2019•0 citations
Recent studies of the global phase diagram of quantum-critical heavy-fermion metals prompt consideration of the interplay between the Kondo interactions and quantum fluctuations of the local moments alone. Toward this goal, we study a Bose-Fermi Kondo model (BFKM) with Ising anisotropy in the presence of a local transverse field that generates quantum fluctuations in the local-moment sector. We apply the numerical renormalization-group method to the case of a sub-Ohmic bosonic bath exponent and a constant conduction-electron density of states. Starting in the Kondo phase at zero transverse field, there is a smooth crossover with increasing transverse field from a fully screened to a fully polarized impurity spin. By contrast, if the system starts in its localized phase, then increasing the transverse field causes a continuous, Kondo-destruction transition into the partially polarized Kondo phase. The critical exponents at this quantum phase transition exhibit hyperscaling and take essentially the same values as those of the BFKM in zero transverse field. The many-body spectrum at criticality varies continuously with the bare transverse field, indicating a line of critical points. We discuss implications of these results for the global phase diagram of the Kondo lattice model.
In quantum critical heavy fermion systems, local moments are coupled to both collective spin fluctuations and conduction electrons. As such, the Bose-Fermi Kondo model, describing the coupling of a local moment to both a bosonic and a fermionic bath, has been of extensive interest. For the model in the presence of SU(2) spin rotational symmetry, questions have been raised about its phase diagram. Here we develop a version of continuous-time Quantum Monte Carlo (CT-QMC) method suitable for addressing this issue; this procedure can reach sufficiently low temperatures while preserving the SU(2) symmetry. Using this method for the Bose-Fermi Anderson model, we clarify the renormalization-group fixed points and the phase diagram for the case with a constant fermionic-bath density of states and a power-law bosonic-bath spectral function ρb(ω)∝ωs\rho_{b}(\omega) \propto \omega^{s}ρb​(ω)∝ωs (0<s<10<s<10<s<1). We find two types of Kondo destruction QCP, depending on the power-law exponent sss in the bosonic bath spectrum. For s∗<s<1s^{*}<s<1s∗<s<1, both types of QCPs exist and, in the parameter regime accessible by an analytical ϵ\epsilonϵ-expansion renormalization-group calculation (here ϵ=1−s\epsilon=1-sϵ=1−s), the CT-QMC result is fully consistent with prior predictions by the latter method. For s<s∗s<s^{*}s<s∗, there is only one type of QCP. At both type of Kondo destruction QCPs, we find that the exponent of the local spin susceptibility η\etaη obeys the relation η=ϵ\eta=\epsilonη=ϵ, which has important implications for Kondo destruction QCP in the Kondo lattice problem.