Rene Rodrigues Montenegro Filho

@ufpe.br

Professor Physics Department
Universidade Federal de Pernambuco

Rene Rodrigues Montenegro Filho


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https://researchid.co/rene.montenegro

RESEARCH, TEACHING, or OTHER INTERESTS

Condensed Matter Physics, Statistical and Nonlinear Physics
17

Scopus Publications

251

Scholar Citations

10

Scholar h-index

10

Scholar i10-index

Scopus Publications

  • Trimers in the extended Hubbard model
    R. R. Montenegro-Filho, D. R. B. Silva, D. Cogollo, M. D. Coutinho-Filho
    Physical Review B, 2025
  • Mixed-spin Heisenberg ladders in a magnetic field
    D. S. Almeida, A. S. Bibiano-Filho, W. M. da Silva, R. R. Montenegro-Filho
    Physical Review E, 2025
    In this work, we study alternating mixed-spin (s,S) Heisenberg ladders in the magnetic field h density matrix renormalization group and linear spin-wave calculations. The h versus interchain coupling J_{⊥} phase diagram for the (1/2,1) case is investigated in detail. In particular, we demonstrate the compatibility between the critical line estimates and magnetic ordering by analyzing chains with variable values of J_{⊥} and of h along the chain, J_{⊥} and h scans, and considering the usual case of chains with uniform couplings. The magnetization plateau at 1/3 of saturation magnetization, 1/3 plateau, is observed for J_{⊥}>0 and in a limited range for J_{⊥}<0. The critical Kosterlitz-Thouless transition point, where the 1/3 plateau closes, is identified through a finite-size analysis of the transverse spin correlation functions.
  • Quantum bicritical point and phase separation in a frustrated Heisenberg ladder
    D. S. Almeida, R. R. Montenegro-Filho
    Physical Review B, 2023
    We use the density matrix renormalization group (DMRG) and a hard-core boson map to investigate the quantum phase transitions present in the phase diagram of the frustrated Heisenberg ladder in a magnetic field. The quantum bicritical point is observed at the end of a first-order transition line, which is at the meeting of the two second-order transition lines that bound the fully polarized plateau. The characterization of the bicritical point was made using a hard-core boson mapping of the low-energy excitations from the fully polarized phase and through DMRG by studying the probability density of finding the rung spins in a singlet or a triplet state with zero spin component along the magnetic field. In particular, we give conditions for the exchange couplings for the presence of the first-order transition line and the bicritical point in the phase diagram. Moreover, we unveil the phase-separated states for magnetization values inside the magnetization jump and, in particular, the dependence on the system size of the energy curve as a function of magnetization. Finite-size scaling analysis of the transverse spin correlation functions has been used to estimate the critical points of the Kosterlitz-Thouless transitions from the fractional magnetization plateau $m=1/2$ to the respective gapless Luttinger liquid phases for some sets of parameters.
  • Ground-state phase diagram and thermodynamics of coupled trimer chains
    R. R. Montenegro-Filho, E. J. P. Silva-Júnior, M. D. Coutinho-Filho
    Physical Review B, 2022
    The density matrix renormalization group and quantum Monte Carlo method are used to describe coupled trimer chains in a magnetic field h . The Hamiltonian contains exchange terms involving the intra-trimer coupling J 1 (taken as the unit of energy) and the inter-trimer coupling J 2 , plus the Zeeman interaction for a magnetic field h along the z direction. Results for the magnetization per trimer m are calculated in regimes of positive and negative values of the ratio J = J 2 /J 1 , from which the rich field-induced ground state phase diagram h versus J is derived, with the presence of Luttinger liquid, the 1/3 – plateau ( m = 1 / 2), and the one of fully polarized magnetization ( m = 3 / 2). Also, the zero-field Lanczos calculation of spin-wave dispersion from the 1/3 – plateau for S z = 1 is shown at the previous regimes of J values. In addition, we also report on the decay of correlation functions of trimers along open chains, as well as the average two-magnon distribution. The ground state is ferrimagnetic for 0 < J ≤ 1, and is a singlet for − 1 ≤ J < 0. In the singlet phase, the spin correlation functions along the legs present an antiferromagnetic power-law decay, similar to the spin-1/2 linear chain, thus suggesting that the ground state is made of three coupled antiferromagnetically oriented chains. In the singlet phase, the dimensionless thermal magnetic susceptibility per site normalized by 1 / | J | gets closer to 1 /π 2 as the temperature T → 0. For the ferrimagnetic phase, we fit the susceptibility to the experimental data for the compound Pb 3 Cu 3 (PO 4 ) 4 and estimate the model exchange couplings: J 1 = 74 . 8K and J = 0 . 4. These values imply a range of energies for the magnon excitations that are in accord with the data from neutron scattering experiments on Pb 3 Cu 3 (PO 4 ) 4 for two excitation modes. The 1/3 – plateau closes only at 1 / | J | = 0 with J < 0.
  • Role of density-dependent magnon hopping and magnon-magnon repulsion in ferrimagnetic spin-(1/2, S) chains in a magnetic field
    W. M. da Silva, R. R. Montenegro-Filho
    Physical Review B, 2021
    s/S, with s = 1/2, considering the fully polarized magnetization as the boson vacuum. The singleparticle Hamiltonian is a Rice-Mele model with uniform hopping and modified boundaries, while the interactions have a correlated (density-dependent) hopping term and magnon-magnon repulsion. The magnon-magnon repulsion increases the many-magnon energy and the density-dependent hopping decreases the kinetic energy. We use density matrix renormalization group calculations to investigate the effects of these two interaction terms in the bosonic model, and display the quantitative agreement between the results from the spin model and the full bosonic approximation. In particular, we verify the good accordance in the behavior of the edge states, associated with the ferrimagnetic plateau, from the spin and from the bosonic models. Furthermore, we show that the boundary magnon density strongly depends on the interactions and particle statistics..
  • Topology of many-body edge and extended quantum states in an open spin chain: 1/3 plateau, Kosterlitz-Thouless transition, and Luttinger liquid
    R. R. Montenegro-Filho, F. S. Matias, M. D. Coutinho-Filho
    Physical Review B, 2020
    Quantum many-body edge and extended magnon excitations from the 1/3 plateau of the anisotropic Heisenberg model on an open ${AB}_{2}$ chain in a magnetic field $h$ are unveiled using the density matrix renormalization group and exact diagonalization. By tuning both the anisotropy and $h$ in the rich phase diagram, the edge states penetrate in the bulk, whose gap closes in a symmetry-protected topological Kosterlitz-Thouless transition. Also, we witness the squeezed chain effect, the breaking of the edge state degeneracy, and a topological change of the excitations from gapped magnons with quadratic long-wavelength dispersion to a linear spinon dispersion in the Luttinger liquid gapless phase as the anisotropy $\\ensuremath{\\lambda}$ approaches the critical point from the $\\ensuremath{\\lambda}g0$ side of the phase diagram.
  • Magnetic phase separation in a frustrated ferrimagnetic chain under a magnetic field
    A. M. do Nascimento-Junior, R. R. Montenegro-Filho
    Physical Review B, 2019
    We use density matrix renormalization group to study the first-order quantum phase transition induced by a magnetic field $h$ in a frustrated ferrimagnetic chain. The magnetization ($m$) curve as a function of $h$ presents a macroscopic jump and the energy curve as a function of $m$ has two global minima. We characterize the two competing phases and study the phase-separated states in the coexistence region. Also, we observe that the transition is accompanied by an increase in the number of itinerant singlet pairs between sites in the unit cells of the chain. Finally, we identify the critical point at the end of the first-order transition line and a crossover line.
  • Fractional exclusion statistics and thermodynamics of the Hubbard chain in the spin-incoherent Luttinger liquid regime
    Carlindo Vitoriano, R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review B, 2018
    Bethe ansatz and bosonization procedures are used to describe the thermodynamics of the strong-coupled Hubbard chain in the \\textit{spin-incoherent} Luttinger liquid (LL) regime: $J(\\equiv 4t^2/U)\\ll k_B T\\ll E_F$, where $t$ is the hopping amplitude, $U(\\gg t)$ is the repulsive on-site Coulomb interaction, and $k_B T (E_F\\sim t)$ is the thermal (Fermi) energy. We introduce a fractional Landau LL approach, whose $U=\\infty$ fixed point is exactly mapped onto an ideal gas with two species obeying the Haldane-Wu \\textit{exclusion} fractional statistics. This phenomenological approach sheds light on the behavior of several thermodynamic properties in the spin-incoherent LL regime: specific heat, charge compressibility, magnetic susceptibility, and Drude weight. In fact, besides the hopping (mass) renormalization, the fractional Landau LL parameters, due to quasiparticle interaction, are determined and relationships with velocities of holons and spinons are unveiled. The specific heat thus obtained is in very good agreement with previous density matrix renormalization group (DMRG) simulations of the $t$-$J$ model in the spin-incoherent regime. A phase diagram is provided and two thermodynamic paths to access this regime clarifies both the numerical and analytical procedures. Further, we show that the high-$T$ limit of the fractional Landau LL entropy and chemical potential exhibit the expected results of the $t$-$J$ model, under the condition $U\\gg k_B T$. Lastly, finite-temperature Lanczos simulations of the single-particle distribution function confirm the characteristics of the spin-incoherent regime and the high-$T$ limit observed in previous DMRG studies.
  • Magnetic-fielderature phase diagram of alternating ferrimagnetic chains: Spin-wave theory from a fully polarized vacuum
    W. M. da Silva, R. R. Montenegro-Filho
    Physical Review B, 2017
    Quantum critical (QC) phenomena can be accessed by studying quantum magnets under an applied magnetic field ($B$). The QC points are located at the endpoints of magnetization plateaus and separate gapped and gapless phases. In one dimension, the low-energy excitations of the gapless phase form a Luttinger liquid (LL), and crossover lines bound insulating (plateau) and LL regimes, as well as the QC regime. Alternating ferrimagnetic chains have a spontaneous magnetization at $T=0$ and gapped excitations at zero field. Besides the plateau at the fully polarized (FP) magnetization; due to the gap, there is another magnetization plateau at the ferrimagnetic (FRI) magnetization. We develop spin-wave theories to study the thermal properties of these chains under an applied magnetic field: one from the FRI classical state, and other from the FP state, comparing their results with quantum Monte Carlo data. We deepen the theory from the FP state, obtaining the crossover lines in the $T$ vs. $B$ low-$T$ phase diagram. In particular, from local extreme points in the susceptibility and magnetization curves, we identify the crossover between an LL regime formed by excitations from the FRI state to another built from excitations of the FP state. These two LL regimes are bounded by an asymmetric dome-like crossover line, as observed in the phase diagram of other quantum magnets under an applied magnetic field.
  • Magnetic and nonmagnetic phases in doped AB2 t-J Hubbard chains MAGNETIC and NONMAGNETIC PHASES in DOPED ... R. R. MONTENEGRO-FILHO and M. D. COUTINHO-FILHO
    R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review B Condensed Matter and Materials Physics, 2014
    We discuss the rich phase diagram of doped AB2 $t-J$ chains by using data from density matrix renormalization group and exact diagonalization techniques. The $J$ vs $\\delta$ (hole doping) phase diagram exhibits regions of itinerant ferrimagnetism, incommensurate, resonating valence bond and Nagaoka states, phase separation, and Luttinger liquid (LL) physics. Several features are highlighted, such as the modulated ferrimagnetic structure, the occurrence of Nagaoka spin polarons in the underdoped regime and small values of $J=4t^2/U$, where $t$ is the first-neighbor hopping amplitude and $U$ is the on-site repulsive Coulomb interaction, incommensurate structures with nonzero magnetization, and strong-coupling LL physics in the high-doped regime. We also verify that relevant findings are in agreement with the corresponding findings in square and n-leg ladder lattices. In particular, we mention the instability of Nagaoka ferromagnetism against $J$ and $\\delta$.
  • Interface dynamics of immiscible two-phase lattice-gas cellular automata: A model with random dynamic scatterers and quenched disorder in two dimensions
    R. M. Azevedo, R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review E Statistical Nonlinear and Soft Matter Physics, 2013
  • Quantum phase transitions in alternating spin-(1/2, 5/2) Heisenberg chains
    Antônio S F Tenório, R R Montenegro-Filho, M D Coutinho-Filho
    Journal of Physics Condensed Matter, 2011
  • Quantum rotors on the AB2 chain with competing interactions
    Antônio S. F. Tenório, R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review B Condensed Matter and Materials Physics, 2009
  • Frustration-induced quantum phase transitions in a quasi-one-dimensional ferrimagnet: Hard-core boson map and the Tonks-Girardeau limit
    R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review B Condensed Matter and Materials Physics, 2008
  • Magnetism and electronic correlations in quasi-one-dimensional compounds
    M. D. Coutinho-Filho, R. R. Montenegro-Filho, E. P. Raposo, C. Vitoriano, M. H. Oliveira
    Journal of the Brazilian Chemical Society, 2008
  • Doped a B2 Hubbard chain: Spiral, Nagaoka and resonating-valence-bond states, phase separation, and Luttinger-liquid behavior
    R. R. Montenegro-Filho, M. D. Coutinho-Filho
    Physical Review B Condensed Matter and Materials Physics, 2006
  • Quasi-one-dimensional quantum ferrimagnets
    R.R. Montenegro-Filho, M.D. Coutinho-Filho
    Physica A Statistical Mechanics and Its Applications, 2005

RECENT SCHOLAR PUBLICATIONS

  • Trimers in the extended Hubbard model
    RR Montenegro-Filho, DRB Silva, D Cogollo, MD Coutinho-Filho
    Physical Review B 111 (5), 054416 , 2025
    2025
    Citations: 1
  • Mixed-spin Heisenberg ladders in a magnetic field
    DS Almeida, AS Bibiano-Filho, WM da Silva, RR Montenegro-Filho
    Physical Review E 111 (1), 014149 , 2025
    2025
    Citations: 2
  • Quantum bicritical point and phase separation in a frustrated Heisenberg ladder
    DS Almeida, RR Montenegro-Filho
    Physical Review B 108 (22), 224433 , 2023
    2023
    Citations: 4
  • Ground-state phase diagram and thermodynamics of coupled trimer chains
    RR Montenegro-Filho, EJP Silva-Júnior, MD Coutinho-Filho
    Physical Review B 105 (13), 134423 , 2022
    2022
    Citations: 11
  • Spin-wave theory from the fully polarized vacuum for ferrimagnetic spin-(1/2, S) chains in a magnetic field
    R Montenegro, W da Silva
    APS March Meeting Abstracts 2022, B64. 010 , 2022
    2022
  • Role of density-dependent magnon hopping and magnon-magnon repulsion in ferrimagnetic spin-(1/2, ) chains in a magnetic field
    WM Da Silva, RR Montenegro-Filho
    Physical Review B 103 (5), 054432 , 2021
    2021
    Citations: 9
  • Topology of many-body edge and extended quantum states in an open spin chain: 1/3 plateau, Kosterlitz-Thouless transition, and Luttinger liquid
    RR Montenegro-Filho, FS Matias, MD Coutinho-Filho
    Physical Review B 102 (3), 035137 , 2020
    2020
    Citations: 24
  • Magnetic phase separation in a frustrated ferrimagnetic chain under a magnetic field
    AM do Nascimento-Junior, RR Montenegro-Filho
    Physical Review B 99 (6), 064404 , 2019
    2019
    Citations: 12
  • Magnetic field-temperature phase diagram of ferrimagnetic alternating chains: spin-wave theory from a fully polarized vacuum
    WM da Silva, RR Montenegro-Filho
    arXiv preprint arXiv:1808.09240 , 2018
    2018
    Citations: 1
  • Fractional exclusion statistics and thermodynamics of the Hubbard chain in the spin-incoherent Luttinger liquid regime
    C Vitoriano, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B 98 (8), 085130 , 2018
    2018
    Citations: 6
  • Magnetic-field–temperature phase diagram of alternating ferrimagnetic chains: Spin-wave theory from a fully polarized vacuum
    WM da Silva, RR Montenegro-Filho
    Physical Review B 96 (21), 214419 , 2017
    2017
    Citations: 15
  • Magnetic and nonmagnetic phases in doped AB2 tJ Hubbard chains
    RR Montenegro-Filho, MD Coutinho-Filho
    arXiv preprint arXiv:1504.01951 , 2015
    2015
    Citations: 15
  • Magnetic and Nonmagnetic Phases in Doped AB2 tJ Chains
    RR Montenegro-Filho, MD Coutinho-Filho
    arXiv preprint arXiv:1504.01951 , 2015
    2015
  • Interface dynamics of immiscible two-phase lattice-gas cellular automata: A model with random dynamic scatterers and quenched disorder in two dimensions
    RM Azevedo, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review E—Statistical, Nonlinear, and Soft Matter Physics 88 (3 … , 2013
    2013
    Citations: 1
  • Quantum phase transitions in alternating spin-(,) Heisenberg chains
    ASF Tenório, RR Montenegro-Filho, MD Coutinho-Filho
    Journal of Physics: Condensed Matter 23 (50), 506003 , 2011
    2011
    Citations: 24
  • Magnetic field-temperature phase diagram of the spin-1/2/spin-5/2 chain
    RR Montenegro-Filho, ASF Tenorio, MD Coutinho-Filho
    Sociedade Brasileira de Fisica (SBF), Sao Paulo, SP (Brazil) , 2011
    2011
  • Quantum rotors on the chain with competing interactions
    ASF Tenório, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 80 (5), 054409 , 2009
    2009
    Citations: 9
  • Frustration-induced quantum phase transitions in a quasi-one-dimensional ferrimagnet: Hard-core boson map and the Tonks-Girardeau limit
    RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 78 (1), 014418 , 2008
    2008
    Citations: 36
  • Magnetism and electronic correlations in quasi-one-dimensional compounds
    MD Coutinho-Filho, RR Montenegro-Filho, EP Raposo, C Vitoriano, ...
    Journal of the Brazilian Chemical Society 19, 232-244 , 2008
    2008
    Citations: 20
  • Doped Hubbard chain: Spiral, Nagaoka and resonating-valence-bond states, phase separation, and Luttinger-liquid behavior
    RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 74 (12), 125117 , 2006
    2006
    Citations: 33

MOST CITED SCHOLAR PUBLICATIONS

  • Frustration-induced quantum phase transitions in a quasi-one-dimensional ferrimagnet: Hard-core boson map and the Tonks-Girardeau limit
    RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 78 (1), 014418 , 2008
    2008
    Citations: 36
  • Doped Hubbard chain: Spiral, Nagaoka and resonating-valence-bond states, phase separation, and Luttinger-liquid behavior
    RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 74 (12), 125117 , 2006
    2006
    Citations: 33
  • Quasi-one-dimensional quantum ferrimagnets
    RR Montenegro-Filho, MD Coutinho-Filho
    Physica A: Statistical Mechanics and its Applications 357 (1), 173-180 , 2005
    2005
    Citations: 28
  • Topology of many-body edge and extended quantum states in an open spin chain: 1/3 plateau, Kosterlitz-Thouless transition, and Luttinger liquid
    RR Montenegro-Filho, FS Matias, MD Coutinho-Filho
    Physical Review B 102 (3), 035137 , 2020
    2020
    Citations: 24
  • Quantum phase transitions in alternating spin-(,) Heisenberg chains
    ASF Tenório, RR Montenegro-Filho, MD Coutinho-Filho
    Journal of Physics: Condensed Matter 23 (50), 506003 , 2011
    2011
    Citations: 24
  • Magnetism and electronic correlations in quasi-one-dimensional compounds
    MD Coutinho-Filho, RR Montenegro-Filho, EP Raposo, C Vitoriano, ...
    Journal of the Brazilian Chemical Society 19, 232-244 , 2008
    2008
    Citations: 20
  • Magnetic-field–temperature phase diagram of alternating ferrimagnetic chains: Spin-wave theory from a fully polarized vacuum
    WM da Silva, RR Montenegro-Filho
    Physical Review B 96 (21), 214419 , 2017
    2017
    Citations: 15
  • Magnetic and nonmagnetic phases in doped AB2 tJ Hubbard chains
    RR Montenegro-Filho, MD Coutinho-Filho
    arXiv preprint arXiv:1504.01951 , 2015
    2015
    Citations: 15
  • Magnetic phase separation in a frustrated ferrimagnetic chain under a magnetic field
    AM do Nascimento-Junior, RR Montenegro-Filho
    Physical Review B 99 (6), 064404 , 2019
    2019
    Citations: 12
  • Ground-state phase diagram and thermodynamics of coupled trimer chains
    RR Montenegro-Filho, EJP Silva-Júnior, MD Coutinho-Filho
    Physical Review B 105 (13), 134423 , 2022
    2022
    Citations: 11
  • Role of density-dependent magnon hopping and magnon-magnon repulsion in ferrimagnetic spin-(1/2, ) chains in a magnetic field
    WM Da Silva, RR Montenegro-Filho
    Physical Review B 103 (5), 054432 , 2021
    2021
    Citations: 9
  • Quantum rotors on the chain with competing interactions
    ASF Tenório, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B—Condensed Matter and Materials Physics 80 (5), 054409 , 2009
    2009
    Citations: 9
  • Fractional exclusion statistics and thermodynamics of the Hubbard chain in the spin-incoherent Luttinger liquid regime
    C Vitoriano, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review B 98 (8), 085130 , 2018
    2018
    Citations: 6
  • Quantum bicritical point and phase separation in a frustrated Heisenberg ladder
    DS Almeida, RR Montenegro-Filho
    Physical Review B 108 (22), 224433 , 2023
    2023
    Citations: 4
  • Mixed-spin Heisenberg ladders in a magnetic field
    DS Almeida, AS Bibiano-Filho, WM da Silva, RR Montenegro-Filho
    Physical Review E 111 (1), 014149 , 2025
    2025
    Citations: 2
  • Trimers in the extended Hubbard model
    RR Montenegro-Filho, DRB Silva, D Cogollo, MD Coutinho-Filho
    Physical Review B 111 (5), 054416 , 2025
    2025
    Citations: 1
  • Magnetic field-temperature phase diagram of ferrimagnetic alternating chains: spin-wave theory from a fully polarized vacuum
    WM da Silva, RR Montenegro-Filho
    arXiv preprint arXiv:1808.09240 , 2018
    2018
    Citations: 1
  • Interface dynamics of immiscible two-phase lattice-gas cellular automata: A model with random dynamic scatterers and quenched disorder in two dimensions
    RM Azevedo, RR Montenegro-Filho, MD Coutinho-Filho
    Physical Review E—Statistical, Nonlinear, and Soft Matter Physics 88 (3 … , 2013
    2013
    Citations: 1
  • Spin-wave theory from the fully polarized vacuum for ferrimagnetic spin-(1/2, S) chains in a magnetic field
    R Montenegro, W da Silva
    APS March Meeting Abstracts 2022, B64. 010 , 2022
    2022
  • Magnetic and Nonmagnetic Phases in Doped AB2 tJ Chains
    RR Montenegro-Filho, MD Coutinho-Filho
    arXiv preprint arXiv:1504.01951 , 2015
    2015