112 citations · 419 across the 15 of their papers we have counts for
15 papers
Inductive Bias for Emergent Communication in a Continuous Setting
John Isak Fjellvang Villanger, Troels Arnfred Bojesen
We study emergent communication in a multi-agent reinforcement learning setting, where the agents solve cooperative tasks and have access to a communication channel. The communicat…
Thermodynamic classification of three-dimensional Kitaev spin liquids
Tim Eschmann, Petr A. Mishchenko, Kevin O'Brien +5
In the field of frustrated magnetism, Kitaev models provide a unique framework to study the phenomena of spin fractionalization and emergent lattice gauge theories in two and three…
Chiral spin liquids with crystalline gauge order in a three-dimensional Kitaev model
Petr A. Mishchenko, Yasuyuki Kato, Kevin O'Brien +5
Chiral spin liquids (CSLs) are time-reversal symmetry breaking ground states of frustrated quantum magnets that show no long-range magnetic ordering, but instead exhibit topologica…
Thermodynamics of a gauge-frustrated Kitaev spin liquid
T. Eschmann, P. A. Mishchenko, T. A. Bojesen +4
Two- and three-dimensional Kitaev magnets are prototypical frustrated quantum spin systems, in which the original spin degrees of freedom fractionalize into Majorana fermions and a…
Policy Guided Monte Carlo: Reinforcement Learning Markov Chain Dynamics
Troels Arnfred Bojesen
We introduce \textit{Policy Guided Monte Carlo} (PGMC), a computational framework using reinforcement learning to improve Markov chain Monte Carlo (MCMC) sampling. The methodology…
Quantum spin ice under a [111] magnetic field: from pyrochlore to kagomé
Troels Arnfred Bojesen, Shigeki Onoda
Quantum spin ice, modeled for magnetic rare-earth pyrochlores, has attracted great interest for hosting a U(1) quantum spin liquid, which involves spin-ice monopoles as gapped deco…
Lattices of double-quanta vortices and chirality inversion in superconductors
Julien Garaud, Egor Babaev, Troels Arnfred Bojesen +1
We investigate the magnetization processes of a standard Ginzburg-Landau model for chiral p-wave superconducting states in an applied magnetic field. We find that the phase diagram…
Topological semimetals protected by off-centered symmetries in nonsymmorphic crystals
Bohm-Jung Yang, Troels Arnfred Bojesen, Takahiro Morimoto +1
Topological semimetals have energy bands near the Fermi energy sticking together at isolated points/lines/planes in the momentum space, which are often accompanied by stable surfac…
Josephson-frustrated superconductors in a magnetic field
Troels Arnfred Bojesen, Asle Sudbø
We study the effect of an externally imposed rotation or magnetic field on frustrated multiband superconductors/superfluids. The frustration originates with multiple superconductin…
Fluctuation effects in phase-frustrated multiband superconductors
Troels Arnfred Bojesen, Asle Sudbø
We compare the phase-diagrams of an effective theory of a three-dimensional multi-band superconductor obtained within standard and cluster mean-field theories, and in large-scale M…
Phase transitions and anomalous normal state in superconductors with broken time reversal symmetry
Troels Arnfred Bojesen, Egor Babaev, Asle Sudbø
Using Monte Carlo simulations, we explore the phase diagram and the phase transitions in $\groupUZ$ -band superconductors with spontaneously broken time-reversal symmetry (also…
Berry phases, current lattices, and suppression of phase transitions in a lattice gauge theory of quantum antiferromagnets
Troels Arnfred Bojesen, Asle Sudbø
We consider a lattice model of two complex scalar matter fields under a CP1 constraint $\abs{z_1}^2+\abs{z_2}^2=1$, minimally coupled to a compact gauge field, with…
Time reversal symmetry breakdown in normal and superconducting states in frustrated three-band systems
Troels Bojesen, Egor Babaev, Asle Sudbø
We discuss the phase diagram and phase transitions in $U(1)\times \groupZ{2}$ three-band superconductors with broken time reversal symmetry. We find that beyond mean field approxim…
Multihistogram Reweighting for Nonequilibrium Markov Processes Using Sequential Importance Sampling Methods
Troels Arnfred Bojesen
We present a multihistogram reweighting technique for nonequilibrium Markov Chains with discrete energies. The method generalizes the single histogram method of Yin et al. [Phys. R…
Phase structure and phase transitions in a three dimensional SU(2) superconductor
Egil V. Herland, Troels A. Bojesen, Egor Babaev +1
We study the three dimensional SU(2)-symmetric noncompact CP1 model, with two charged matter fields coupled minimally to a noncompact Abelian gauge-field. The phase diagram and the…