In-gap spin excitations and finite triplet lifetimes in the dilute singlet ground state system SrCu(2-x)Mgx(BO3)2.

Journal Article

High resolution neutron scattering measurements on a single crystal of SrCu(2-x)Mgx(BO3)2 with x approximately 0.05 reveal the presence of new spin excitations within the gap of this quasi-two-dimensional, singlet ground state system. The application of a magnetic field induces Zeeman-split states associated with S=1/2 unpaired spins which are antiferromagnetically correlated with the bulk singlet. Substantial broadening of both the one- and two-triplet excitations in the doped single crystal is observed, as compared with pure SrCu2(BO3)2. Theoretical calculations using a variational algorithm and a single quenched magnetic vacancy on an infinite lattice are shown to qualitatively account for these effects.

Full Text

Duke Authors

Cited Authors

  • Haravifard, S; Dunsiger, SR; El Shawish, S; Gaulin, BD; Dabkowska, HA; Telling, MT; Perring, TG; Bonca, J

Published Date

  • December 14, 2006

Published In

Volume / Issue

  • 97 / 24

Start / End Page

  • 247206 -

PubMed ID

  • 17280317

Electronic International Standard Serial Number (EISSN)

  • 1079-7114

International Standard Serial Number (ISSN)

  • 0031-9007

Digital Object Identifier (DOI)

  • 10.1103/physrevlett.97.247206

Language

  • eng