https://doi.org/10.1140/epjb/e2019-100576-6
Regular Article
Emergent SU(N) symmetry in disordered SO(N) spin chains★
1
Department of Physics and Astronomy, Iowa State University,
Ames,
Iowa 50011, USA
2
Department of Physics and National High Magnetic Field Laboratory, Florida State University,
Tallahassee,
Florida 32306, USA
3
Stewart Blusson Quantum Matter Institute, University of British Columbia,
Vancouver,
British Columbia V6T 1Z4, Canada
4
Département de Physique, Institut Quantique and Regroupement Québécois sur les Matériaux de Pointe, Université de Sherbrooke, Sherbrooke,
Québec
J1K 2R1, Canada
5
Instituto de Física de São Carlos, Universidade de São Paulo, C.P. 369,
São Carlos,
SP 13560-970, Brazil
6
Instituto de Física Gleb Wataghin, Unicamp, Rua Sérgio Buarque de Holanda, 777,
CEP 13083-859
Campinas,
SP, Brazil
a e-mail: hoyos@ifsc.usp.br
Received:
27
November
2019
Received in final form:
17
December
2019
Published online: 28 January 2020
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 emergent SU(N) symmetry are of two kinds: one has a ground state formed of randomly distributed singlets of strongly bound pairs of SO(N) spins (a ‘mesonic’ phase), while the other has a ground state composed of singlets made out of strongly bound integer multiples of N SO(N) spins (a ‘baryonic’ phase). The established mechanism is general and we put forward the cases of N = 2, 3, 4 and 6 as prime candidates for experimental realizations in material compounds and cold-atoms systems. We display universal temperature scaling and critical exponents for susceptibilities distinguishing these phases and characterizing the enlarging of the microscopic symmetries at low energies.
© EDP Sciences / Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2020