Show simple item record

dc.contributor.authorIaizzi, Adamen_US
dc.contributor.authorDamle, Kedaren_US
dc.contributor.authorSandvik, Anders W.en_US
dc.date.accessioned2018-12-06T19:18:13Z
dc.date.available2018-12-06T19:18:13Z
dc.date.issued2017-05-25
dc.identifierhttp://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000401998500001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=6e74115fe3da270499c3d65c9b17d654
dc.identifier.citationAdam Iaizzi, Kedar Damle, Anders W Sandvik. 2017. "Field-driven quantum phase transitions in S=1/2 spin chains." Physical Review B, Volume 95, Issue 17, 174436. https://doi.org/10.1103/PhysRevB.95.174436
dc.identifier.issn2469-9950
dc.identifier.issn2469-9969
dc.identifier.urihttps://hdl.handle.net/2144/32899
dc.description.abstractWe study the magnetization process of a one-dimensional extended Heisenberg model, the J−Q model, as a function of an external magnetic field h. In this model, J represents the traditional antiferromagnetic Heisenberg exchange and Q is the strength of a competing four-spin interaction. Without external field, this system hosts a twofold-degenerate dimerized (valence-bond solid) state above a critical value qc≈0.85 where q≡Q/J. The dimer order is destroyed and replaced by a partially polarized translationally invariant state at a critical field value. We find magnetization jumps (metamagnetism) between the partially polarized and fully polarized state for q>qmin, where we have calculated qmin=29 exactly. For q>qmin, two magnons (flipped spins on a fully polarized background) attract and form a bound state. Quantum Monte Carlo studies confirm that the bound state corresponds to the first step of an instability leading to a finite magnetization jump for q>qmin. Our results show that neither geometric frustration nor spin anisotropy are necessary conditions for metamagnetism. Working in the two-magnon subspace, we also find evidence pointing to the existence of metamagnetism in the unfrustrated J1−J2 chain (J1>0,J2<0), but only if J2 is spin anisotropic. In addition to the studies at zero temperature, we also investigate quantum-critical scaling near the transition into the fully polarized state for q≤qmin at T>0. While the expected “zero-scale-factor” universality is clearly seen for q=0 and q≪qmin, for q closer to qmin we find that extremely low temperatures are required to observe the asymptotic behavior, due to the influence of the tricritical point at qmin. In the low-energy theory, one can expect the quartic nonlinearity to vanish at qmin and a marginal sixth-order term should govern the scaling, which leads to a crossover at a temperature T∗(q) between logarithmic tricritical scaling and zero-scale-factor universality, with T∗(q)→0 when q→qmin.en_US
dc.description.sponsorshipThe work of A.I. and A.W.S. was supported by the NSF under Grant No. DMR-1410126. A.I. acknowledges support from the APS-IUSSTF Physics PhD Student Visitation Program for a visit to K.D. at the Tata Institute of Fundamental Research in Mumbai. The computational work reported in this paper was performed in part on the Shared Computing Cluster administered by Boston University's Research Computing Services. We gratefully acknowledge the help of H.-G. Luo, B.B. Mao, and C. Cheng who helped us discover an error in the J<INF>1</INF>-J<INF>2</INF> calculation in our original preprint. (DMR-1410126 - NSF; APS-IUSSTF Physics PhD Student Visitation Program)en_US
dc.languageEnglish
dc.publisherAmerican Physical Societyen_US
dc.relation.ispartofPhysical Review B
dc.subjectScience & technologyen_US
dc.subjectTechnologyen_US
dc.subjectPhysical sciencesen_US
dc.subjectPhysics, Applieden_US
dc.subjectPhysics, Condensed Matteren_US
dc.subjectMaterials scienceen_US
dc.subjectPhysicsen_US
dc.subjectHeisenberg antiferromagnetic chainen_US
dc.subjectMetamagnetismen_US
dc.subjectCondensed matter physicsen_US
dc.titleField-driven quantum phase transitions in S=1/2 spin chainsen_US
dc.typeArticleen_US
dc.description.versionAccepted manuscripten_US
dc.identifier.doi10.1103/PhysRevB.95.174436
pubs.elements-sourceweb-of-scienceen_US
pubs.notesEmbargo: Not knownen_US
pubs.organisational-groupBoston Universityen_US
pubs.organisational-groupBoston University, College of Arts & Sciencesen_US
pubs.organisational-groupBoston University, College of Arts & Sciences, Department of Physicsen_US
pubs.publication-statusPublisheden_US
dc.identifier.orcid0000-0002-5638-4619 (Sandvik, Anders W)


This item appears in the following Collection(s)

Show simple item record