76 citations · 794 across the 49 of their papers we have counts for
22 papers · 1 filter
Effect of long-range hopping on dynamic quantum phase transitions of an exactly solvable free-fermion model: Nonanalyticities at almost all times
J. C. Xavier, José A. Hoyos
In this work, we investigate quenches in a free-fermion chain with long-range hopping which decay with the distance with an exponent and has range . By exploring the exact s…
The phase diagram of a frustrated Heisenberg model: from disorder to order and back again
Michel M. J. Miranda, Igor C. Almeida, Eric C. Andrade +1
We study the effects of bond and site disorder in the classical - Heisenberg model on a square lattice in the order-by-disorder frustrated regime $2J_{2}>\left|J_{1}\…
Inhomogeneous mean-field approach to collective excitations in disordered interacting bosons
Martin Puschmann, João C. Getelina, José A. Hoyos +1
We develop an inhomogeneous quantum mean-field approach to the behavior of collective excitations across the superfluid-Mott glass quantum phase transition in two dimensions, compl…
Adaptive Density Matrix Renormalization Group for Disordered Systems
J. C. Xavier, J. A. Hoyos, E. Miranda
We propose a simple modification of the density matrix renormalization group (DMRG) method in order to tackle strongly disordered quantum spin chains. Our proposal, akin to the ide…
Emergent dimerization and localization in disordered quantum chains
André P. Vieira, José A. Hoyos
We uncover a novel mechanism for inducing a gapful phase in interacting many-body quantum chains. The mechanism is nonperturbative, being triggered only in the presence of both str…
Highly-symmetric random one-dimensional spin models
V. L. Quito, Pedro L. S. Lopes, José A. Hoyos +1
The interplay of disorder and interactions is a challenging topic of condensed matter physics, where correlations are crucial and exotic phases develop. In one spatial dimension, a…
Emergent SU(N) symmetry in disordered SO(N) spin chains
V. L. Quito, Pedro L. S. Lopes, José A. Hoyos +1
Strongly disordered spin chains invariant under the SO(N) group are shown to display random-singlet phases with emergent SU(N) symmetry without fine tuning. The phases with emergen…
Cluster-glass phase in pyrochlore XY antiferromagnets with quenched disorder
Eric C. Andrade, José A. Hoyos, Stephan Rachel +1
We study the impact of quenched disorder (random exchange couplings or site dilution) on easy-plane pyrochlore antiferromagnets. In the clean system, order-by-disorder selects a ma…
Strong-disorder renormalization group study of the Anderson localization transition in three and higher dimensions
Hossein Javan Mard, Jose A. Hoyos, Eduardo Miranda +1
We implement an efficient strong-disorder renormalization-group (SDRG) procedure to study disordered tight-binding models in any dimension and on the Erdos-Renyi random graphs, whi…
Strong-randomness phenomena in quantum Ashkin-Teller models
Hatem Barghathi, Fawaz Hrahsheh, José A. Hoyos +2
The -color quantum Ashkin-Teller spin chain is a prototypical model for the study of strong-randomness phenomena at first-order and continuous quantum phase transitions. In this…
Emergent SU(3) symmetry in random spin-1 chains
V. L. Quito, José A. Hoyos, E. Miranda
We show that generic SU(2)-invariant random spin-1 chains have phases with an emergent SU(3) symmetry. We map out the full zero-temperature phase diagram and identify two different…
Strong-randomness infinite-coupling phase in a random quantum spin chain
Fawaz Hrahsheh, Rajesh Narayanan, José A. Hoyos +1
We study the ground-state phase diagram of the Ashkin-Teller random quantum spin chain by means of a generalization of the strong-disorder renormalization group. In addition to the…
Rounding of a first-order quantum phase transition to a strong-coupling critical point
Fawaz Hrahsheh, José A. Hoyos, Thomas Vojta
We investigate the effects of quenched disorder on first-order quantum phase transitions on the example of the -color quantum Ashkin-Teller model. By means of a strong-disorder…
Percolation transition in quantum Ising and rotor models with sub-Ohmic dissipation
Manal Al-Ali, José A. Hoyos, Thomas Vojta
We investigate the influence of sub-Ohmic dissipation on randomly diluted quantum Ising and rotor models. The dissipation causes the quantum dynamics of sufficiently large percolat…
Influence of superohmic dissipation on a disordered quantum critical point
Thomas Vojta, J. A. Hoyos, Priyanka Mohan +1
We investigate the combined influence of quenched randomness and dissipation on a quantum critical point with O(N) order-parameter symmetry. Utilizing a strong-disorder renormaliza…
Magnetic Grueneisen ratio of the random transverse-field Ising chain
Thomas Vojta, J. A. Hoyos
The magnetic analog of the Grüneisen parameter, i.e., the magnetocaloric effect, is a valuable tool for studying field-tuned quantum phase transitions. We determine the magnetic Gr…
Smeared quantum phase transition in the dissipative random quantum Ising model
Thomas Vojta, J. A. Hoyos
We investigate the quantum phase transition in the random transverse-field Ising model under the influence of Ohmic dissipation. To this end, we numerically implement a strong-diso…
Valence-bond theory of highly disordered quantum antiferromagnets
S. Zhou, J. A. Hoyos, V. Dobrosavljevic +1
We present a large-N variational approach to describe the magnetism of insulating doped semiconductors based on a disorder-generalization of the resonating-valence-bond theory for…
Ordered droplets in quantum magnets with long-range interactions
Thomas Vojta, Jose A Hoyos
A defect coupling to the square of the order parameter in a nearly quantum-critical magnet can nucleate an ordered droplet while the bulk system is in the paramagnetic phase. We st…
Percolation transition and dissipation in quantum Ising magnets
J. A. Hoyos, Thomas Vojta
We study the effects of dissipation on a randomly diluted transverse-field Ising magnet close to the percolation threshold. For weak transverse fields, a novel percolation quantum…
Random Antiferromagnetic SU(N) Spin Chains
J. A. Hoyos, E. Miranda
We analyze random isotropic antiferromagnetic SU(N) spin chains using the real space renormalization group. We find that they are governed at low energies by a universal infinite r…
Phase diagrams and universality classes of random antiferromagnetic spin ladders
J. A. Hoyos, E. Miranda
The random antiferromagnetic two-leg and zigzag spin-1/2 ladders are investigated using the real space renormalization group scheme and their complete phase diagrams are determined…