All Outputs (14)

Crossover from string to cluster dynamics following a field quench in spin ice (2024)
Journal Article
Pal, S., & Powell, S. (2024). Crossover from string to cluster dynamics following a field quench in spin ice. Physical Review B, 109(9), Article 094427. https://doi.org/10.1103/PhysRevB.109.094427

We investigate quench dynamics of spin ice after removal of a strong magnetic field along the [100] crystal direction, using Monte Carlo simulations and theoretical arguments. We show how the early time relaxation of the magnetization can be understo... Read More about Crossover from string to cluster dynamics following a field quench in spin ice.

Derivation of field theory for the classical dimer model using bosonization (2023)
Journal Article
Wilkins, N., & Powell, S. (2023). Derivation of field theory for the classical dimer model using bosonization. Physical Review E, 107(5), Article 054126. https://doi.org/10.1103/PhysRevE.107.054126

We derive a field theory for the two-dimensional classical dimer model by applying bosonization to Lieb's (fermionic) transfer-matrix solution. Our constructive approach gives results that are consistent with the well-known height theory, previously... Read More about Derivation of field theory for the classical dimer model using bosonization.

Quantum Kasteleyn transition (2022)
Journal Article
Powell, S. (2022). Quantum Kasteleyn transition. Physical Review B, 105(6), Article 064413. https://doi.org/10.1103/physrevb.105.064413

Dimer models arise as effective descriptions in a variety of physical contexts, and provide paradigmatic examples of systems subject to strong local constraints. Here we present a quantum version of the venerable Kasteleyn model, which has an unusual... Read More about Quantum Kasteleyn transition.

Topological sectors, dimer correlations, and monomers from the transfer-matrix solution of the dimer model (2021)
Journal Article
Wilkins, N., & Powell, S. (2021). Topological sectors, dimer correlations, and monomers from the transfer-matrix solution of the dimer model. Physical Review E, 104(1), Article 014145. https://doi.org/10.1103/physreve.104.014145

We solve the classical square-lattice dimer model with periodic boundaries and in the presence of a field t that couples to the (vector) flux, by diagonalizing a modified version of Lieb's transfer matrix. After deriving the torus partition function... Read More about Topological sectors, dimer correlations, and monomers from the transfer-matrix solution of the dimer model.

Interacting double dimer model on the square lattice (2020)
Journal Article
Wilkins, N., & Powell, S. (2020). Interacting double dimer model on the square lattice. Physical Review B, 102(17), Article 174431. https://doi.org/10.1103/PhysRevB.102.174431

We study phases and transitions of the square-lattice double dimer model, consisting of two coupled replicas of the classical dimer model. As on the cubic lattice, we find a thermal phase transition from the Coulomb phase, a disordered but correlated... Read More about Interacting double dimer model on the square lattice.

Synchronization transition in the double dimer model on the cubic lattice (2019)
Journal Article
Wilkins, N., & Powell, S. (2019). Synchronization transition in the double dimer model on the cubic lattice. Physical Review B, 99(14), Article 144403. https://doi.org/10.1103/PhysRevB.99.144403

We study the classical cubic-lattice double dimer model, consisting of two coupled replicas of the close-packed dimer model, using a combination of theoretical arguments and Monte Carlo simulations. Our results establish the presence of a 'synchroniz... Read More about Synchronization transition in the double dimer model on the cubic lattice.

Emergent SO(5) symmetry at the columnar ordering transition in the classical cubic dimer model (2019)
Journal Article
Sreejith, G., Powell, S., & Nahum, A. (2019). Emergent SO(5) symmetry at the columnar ordering transition in the classical cubic dimer model. Physical Review Letters, 122(8), Article 080601. https://doi.org/10.1103/PhysRevLett.122.080601

The classical cubic-lattice dimer model undergoes an unconventional transition between a columnar crystal and a dimer liquid, in the same universality class as the deconfined quantum critical point in spin-1/2 anti-ferromagnets but with very differen... Read More about Emergent SO(5) symmetry at the columnar ordering transition in the classical cubic dimer model.

Phases of quantum dimers from ensembles of classical stochastic trajectories (2018)
Journal Article
Oakes, T., Powell, S., Castelnovo, C., Lamacraft, A., & Garrahan, J. P. (2018). Phases of quantum dimers from ensembles of classical stochastic trajectories. Physical Review B, 98(6), Article 064302. https://doi.org/10.1103/PhysRevB.98.064302

We study the connection between the phase behaviour of quantum dimers and the dynamics of classical stochastic dimers. At the so-called Rokhsar–Kivelson (RK) point a quantum dimer Hamiltonian is equivalent to the Markov generator of the dynamics of c... Read More about Phases of quantum dimers from ensembles of classical stochastic trajectories.

Quantum slow relaxation and metastability due to dynamical constraints (2018)
Journal Article
Lan, Z., van Horssen, M., Powell, S., & Garrahan, J. P. (2018). Quantum slow relaxation and metastability due to dynamical constraints. Physical Review Letters, 121(4), 1-6. https://doi.org/10.1103/PhysRevLett.121.040603

One of the general mechanisms that give rise to the slow cooperative relaxation characteristic of classical glasses is the presence of kinetic constraints in the dynamics. Here we show that dynamical constraints can similarly lead to slow thermalisat... Read More about Quantum slow relaxation and metastability due to dynamical constraints.

Mean-field theory for confinement transitions and magnetization plateaux in spin ice (2017)
Journal Article
Powell, S. (2017). Mean-field theory for confinement transitions and magnetization plateaux in spin ice. Journal of Physics A: Mathematical and Theoretical, 50(12), https://doi.org/10.1088/1751-8121/aa5bc6

We study phase transitions in classical spin ice at nonzero magnetization, by introducing a mean-field theory designed to capture the interplay between confinement and topological constraints. The method is applied to a model of spin ice in an applie... Read More about Mean-field theory for confinement transitions and magnetization plateaux in spin ice.

Emergence of cooperative dynamics in fully packed classical dimers (2016)
Journal Article
Oakes, T., Garrahan, J. P., & Powell, S. (2016). Emergence of cooperative dynamics in fully packed classical dimers. Physical Review E, 93(3), Article 032129. https://doi.org/10.1103/PhysRevE.93.032129

We study the behavior of classical dimer coverings of the square lattice—a paradigmatic model for systems subject to constraints—evolving under local stochastic dynamics, by means of Monte Carlo simulations and theoretical arguments. We observe clear... Read More about Emergence of cooperative dynamics in fully packed classical dimers.

Scaling dimensions of higher-charge monopoles at deconfined critical points (2015)
Journal Article
Sreejith, G., & Powell, S. (2015). Scaling dimensions of higher-charge monopoles at deconfined critical points. Physical Review B, 92(18), Article 184413. https://doi.org/10.1103/PhysRevB.92.184413

The classical cubic dimer model has a columnar ordering transition that is continuous and described by a critical Anderson–Higgs theory containing an SU(2)-symmetric complex field minimally coupled to a noncompact U(1) gauge theory. Defects in the di... Read More about Scaling dimensions of higher-charge monopoles at deconfined critical points.

Ferromagnetic Coulomb phase in classical spin ice (2015)
Journal Article
Powell, S. (2015). Ferromagnetic Coulomb phase in classical spin ice. Physical Review B, 91(9), Article 094431. https://doi.org/10.1103/PhysRevB.91.094431

Spin ice is a frustrated magnetic system that at low temperatures exhibits a Coulomb phase, a classical spin liquid with topological order and deconfined excitations. This work establishes the presence of a Coulomb phase with coexisting ferromagnetic... Read More about Ferromagnetic Coulomb phase in classical spin ice.

Critical behavior in the cubic dimer model at nonzero monomer density (2014)
Journal Article
Sreejith, G., & Powell, S. (2014). Critical behavior in the cubic dimer model at nonzero monomer density. Physical Review B, 89(1), Article 014404. https://doi.org/10.1103/PhysRevB.89.014404

We study critical behavior in the classical cubic dimer model (CDM) in the presence of a finite density of monomers. With attractive interactions between parallel dimers, the monomer-free CDM exhibits an unconventional transition from a Coulomb phase... Read More about Critical behavior in the cubic dimer model at nonzero monomer density.