By means of the method effective potential, phase transitions from Mott insulating state to either atomic or dimer superfluid in three-body constrained attractive Bose lattice gas are analyzed. Due appearance Feshbach resonance coupling between two kinds order parameters derived potential function, it is found that continuous insulator-to-superfluid can be preempted by first-order ones. Since employed approach provide accurate predictions boundaries strong limit, where emerge, our work hence...

We study the RKKY interaction mediated by helical edge states of a quantum spin Hall insulator in presence Rashba spin-orbital coupling induced an external electric field and electron-electron interaction. show that coupling, contains not only Heisenberg-like Dzyaloshinskii-Moria terms, but also nematic-type term is present absence coupling. Moreover, range functions depend on strength changes modifying power $1/|x|$ dependence functions. In particular, varying or there (impurity) phase...

Abstract In the archetypal lithium-rich cathode compound Li 1.2 Ni 0.13 Co Mn 0.54 O 2 , a major part of capacity is contributed from anionic (O 2−/− ) reversible redox couple and accompanied by transition metal ions migration with detrimental voltage fade. A better understanding these mutual interactions demands for new model that helps to unfold occurrences fade in system. Here we present an alternative approach, cationic reaction dominated material 1.083 0.333 0.083 0.5 reduced lithium...

We investigate theoretically the nonequilibrium finite-frequency current noise in a four-terminal quantum point contact of interacting helical edge states at finite bias voltage. Special focus is put on effects single-particle and two-particle scattering between two fractional charge quasiparticle excitations shown spectra. Via Keldysh perturbative approach, we find that processes depend sensitively Luttinger liquid parameter. Moreover, Fano factors for auto- cross correlations currents...

We study the Josephson-like spin currents between two ferromagnetic metals by deriving effective action of junction. A DC Josephson current with full O(3) symmetry is obtained. By analogy to superconducting junctions, we have shown that a time-independent uniform magnetic field can serve as source AC effect. That is, becomes periodic function time period proportional inverse magnitude external field.

We study the quantum phase transition in an atomic Bose gas near a Feshbach resonance terms of renormalization group. This is characterized by Ising order parameter. show that low temperature regime where fluctuations dominate low-energy physics this first because coupling between parameter and Goldstone mode existing bosonic superfluid. However, when thermal become important, turns into second one, which belongs to three-dimensional universality class. also calculate damping rate collective...

Within the linear flavor-wave theory, we show that due to quantum order-by-disorder mechanism, spin-1 bilinear-biquadratic Heisenberg model on a honeycomb lattice can spontaneously develop columnar dimer order with non-bipartite structure. The low-lying excitations above this novel ground state form several flat bands separated by nonzero energy gaps. Our results suggest phase transition separating dimerized nearby N\'eel-order may be of first order.

We investigate the effects of long-ranged Coulomb interactions in a tilted Dirac semimetal two dimensions by using perturbative renormalization-group method. Depending on magnitude tilting parameter, undoped system can have either Fermi points (type-I) or lines (type-II). Previous studies usually performed transformations integrating out modes with large momenta. This is problematic when surface open, like type-II fermions. In this work, we study interactions, following spirit...

The behavior of the chiral symmetry order parameter 〈\ensuremath{\psi}\ifmmode\bar\else\textasciimacron\fi{}\ensuremath{\psi}〉 in (1+1)-dimensional Schwinger model at finite chemical potential is studied. We find an inhomogeneous condensate.

We study a quantum dot coupled to two edge states of spin Hall insulator through electron tunnelings in the presence Rashba spin-orbital interaction induced by an external electric field. show that if interactions on are repulsive, there possible phases, depending Luttinger liquid parameter $K$. For $1/2<K<1$, low-temperature physics is controlled previously identified two-channel Kondo fixed point. with even stronger repulsive interactions, i.e., $1/4<K<1/2$, system reaches another phase at...

We study the behavior of a topological Josephson junction in which two superconductors are coupled through quantum dot. focus on case with bulk superconducting gap being largest energy scale. Two parameter regimes investigated: weak tunneling between dot and superconductors, near its charge degeneracy point, strong regime transmission is nearly perfect. show that former situation, Andreev spectrum for each sector fixed fermion parity consists only levels, gives rise to nontrivial...

Received 26 January 2022Accepted 21 April 2023DOI:https://doi.org/10.1103/PhysRevLett.130.219701© 2023 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasTopological insulatorsTopological phase transitionTechniquesRenormalization groupCondensed Matter, Materials & Applied Physics

We study the effects of a uniform magnetic field on one-dimensional spin-orbital model in terms effective theories. Two regions are examined: one around SU(4) point (J=K/4) and other with K<<J. found that when $J\leq K/4$, spin orbital correlation functions exhibit power-law decay nonuniversal exponents. In region J>K/4, excitation spectrum has gap. When is beyond some critical value, quantum phase transition occurs. However, K<<J distinct behavior. This results from different structures...

We investigate the effects of quenched disorder on a non-interacting tilted Dirac semimetal in two dimensions. Depending magnitude tilting parameter, system can have either Fermi points (type-I) or lines (type-II). In general, there are three different types disorders for fermions dimensions, namely, random scalar potential, vector potentials along and perpendicular to direction, mass. study weak terms renormalization group, which is performed by integrating out modes with large energies,...

We study the stability of dilute Bose–Fermi and Bose–Bose mixtures with repulsive interactions in one two dimensions terms renormalization group. For mixture, we show that uniform mixture is stable against de-mixing limit. give conditions As a byproduct, also calculate critical temperature for superfluid phase two-dimensional extremely

Recently, the issue of whether Kondo problem in quantum dots at large bias is a weak-coupling or not has been raised. In this paper, we revisit by carefully analyzing corresponding model solvable limit --- Emery-Kivelson line, where various crossover energy scales can be easily identified. We then try to extract scaling behavior from physical correlation functions within spirit ``poor man's scaling.'' Our conclusions support some recent suggestions made Coleman et al. [Phys. Rev. Lett. 86,...

We study an atomic Bose gas with $s$-wave Feshbach resonance in one dimension. Most of the parameter region is occupied by a phase which superfluid fluctuations atoms and molecules are predominant ones, due to being locked Josephson coupling between them. When density difference close zero, two additional phases may exist: two-component Luttinger liquid, contains branches gapless excitations, interchannel charge wave where relative frozen at low energy.

We study the phase diagram of two weakly coupled one-dimensional dipolar boson chains at half-odd-integer fillings. find that system contains a rich diagram. Four different phases are found. They Mott insulators, single-particle resonant superfluid, paired and bond-density or interchain density waves. Moreover, insulating can be further classified according to hidden string order parameter, which is analogous one investigated recently in insulator integer

We study the low-energy properties of one-orbital quantum double-exchange model by using slave fermion formulation. construct a mean-field theory which gives simple explanation for magnetic and thermodynamic ferromagnetic metallic phase in manganites at low energy. The resulting electron spectral function tunneling density states show an incoherent asymmetric peak with weak temperature dependence, addition to quasiparticle peak. also that gauge fluctuations are completely screened due...

The S=1 bilinear-biquadratic Heisenberg model on anisotropic triangular lattices is investigated by several complementary methods. Our focus the stability of three-sublattice spin nematic state against spatial anisotropy. We find that, deviated from case isotropic lattice, quantum fluctuations enhance and order reduced. In limit weakly coupling chains, mapping systems to an effective one-dimensional model, we show that develops at infinitesimal interchain coupling. results provide a complete...

We investigate the effects of long-range Coulomb interactions on low-temperature properties a second-order Dirac semimetal in terms renormalization group. In contrast to first-order semimetal, full rotation symmetry is broken by further additional Hamiltonian, and thus low-energy physics controlled two dimensionless parameters: coupling constant ratio anisotropy parameters. show that first parameter flows zero second fixed value at low energies. Thus, one may calculate physical quantities...

We investigate the effects of a magnetic impurity in multiband touching fermion system, specifically, triple-component semimetal with flat band, which can be realized family transition metal silicides (CoSi family). When chemical potential coincides it is expected that response this system will very different from an ordinary Dirac or Weyl density states at Fermi level vanishes. first determine phase diagram within mean-field approximation. Then, we study local moment regime by employing two...

We study the RKKY interaction mediated by helical edge states of a quantum spin Hall insulator in presence Rashba spin-orbital coupling induced an external electric field and electron-electron interaction. show that coupling, contains not only Heisenberg-like Dzyaloshinskii-Moria terms but also nematic-type term is present originally, with range functions depending on strength coupling. changes modifying power $1/|x|$ dependence functions. In particular, varying or there (impurity) phase...