相关论文: Magnetic Quantum Phase Transitions in a Clean Dira…
Recently, first-order phase transitions have been predicted as an effect of the inclusion of quark anomalous magnetic moment (AMM) in the hot and magnetized Nambu--Jona-Lasinio model (NJL). These transitions appear in the chiral condensate…
In the presence of a chemical potential, the effect of a magnetic field on chiral symmetry breaking goes beyond the well-known magnetic catalysis. Due to a subtle interplay with the chemical potential, the magnetic field may work not only…
This article is aimed at a pedagogical introduction to the physics of quantum phase transitions that is unique to metallic systems. It has been recognized for some time that quantum criticality can result in a breakdown of Landau's Fermi…
An effective field theory is derived for the ferromagnetic transition of diffusive electrons at T=0. The static disorder which leads to diffusive electron dynamics induces an effective long-range interaction between the spins of the form…
Magnetic, dielectric, and magnetoelectric properties in a spin-state transition system are examined, motivated by the recent discovery of a multiferroic behavior in a cobalt oxide. We construct an effective model Hamiltonian based on the…
The possibility of a zero temperature, altermagnetic instability in anisotropic two dimensional electron systems in the diffusive regime is analyzed, in the presence and absence of spin-orbit coupling. Allowing for ferromagnetism, a phase…
We present numerical results on bubble profiles, nucleation rates and time evolution for a weakly first-order quark-hadron phase transition in different expansion scenarios. We confirm the standard picture of a cosmological first-order…
Quantum phase transitions occur at zero temperature when some non-thermal control-parameter like pressure or chemical composition is changed. They are driven by quantum rather than thermal fluctuations. In this review we first give a…
Zero temperature phase transitions not only occur in the bulk of quantum systems, but also at boundaries or impurities. We review recent work on quantum phase transitions in impurity models that are generalizations of the standard Kondo…
We analyze magnetic phases of monolayers of transition metal dichalcogenides that are two-valley materials with electron-electron interactions. The exchange inter-valley scattering makes two-valley systems less stable to the spin…
Baryon-loops vacuum contribution in renormalized models like the Linear sigma model and the Walecka model give rise to large unnatural interaction coefficients, indicating that the quantum vacuum is not adequately described by long-range…
Transitions from classical to quantum behaviour in a spin system with two degenerate ground states separated by twin energy barriers which are asymmetric due to an applied magnetic field are investigated. It is shown that these transitions…
We study the S=1/2 Heisenberg antiferromagnet on a square lattice with nearest-neighbor and plaquette four-spin exchanges (introduced by A.W. Sandvik, Phys. Rev. Lett. {\bf 98}, 227202 (2007).) This model undergoes a quantum phase…
A spatially extended classical system with metastable states subject to weak spatiotemporal noise can exhibit a transition in its activation behavior when one or more external parameters are varied. Depending on the potential, the…
The interplay between charge and spin degrees of freedom in strongly correlated fermionic systems, in particular of Dirac fermions, is a long-standing problem in condensed matter physics. We investigate the competing orders in the…
We report a new manifestation of first-order magnetic transitions in two-dimensional electron systems. This phenomenon occurs in aluminum arsenide quantum wells with sufficiently low carrier densities and appears as a set of hysteretic…
We study a one-dimensional antiferromagnetic-elastic model with magnetic ions having spin $S=3/2$. By extensive DMRG computations and complementary analytical methods, we uncover a first-order transition from a homogeneous or…
We rigorously analyze the quantum phase transition between a metallic and an insulating phase in (non solvable) interacting spin chains or one dimensional fermionic systems. In particular, we prove the persistence of Luttinger liquid…
We shall discuss magnetization and transport measurements in materials exhibiting a broad first-order transition. The phase transitions would be caused by varying magnetic field as well as by varying temperature, and we concentrate on…
Quantum phase transitions between the magnetically ordered and disordered states are studied for the two-dimensional antiferromagnetic quantum spin systems with ladder, plaquette, and mixed-spin structures. Starting with properly chosen…