6533b838fe1ef96bd12a3a5c
RESEARCH PRODUCT
Orbital dimerization inNaTiSi2O6:An orbital analogue of the spin-Peierls phase transition
M. J. KonstantinovićVictor MoshchalkovMasahiko IsobeYutaka UedaZoran B. PopovićJ Van Den Brinksubject
Quantum phase transitionPhysicsPhase transitionCondensed matter physicsPhononFerroicsCondensed Matter PhysicsElectronic Optical and Magnetic Materialssymbols.namesakeNon-bonding orbitalsymbolsCondensed Matter::Strongly Correlated ElectronsValence bond theoryStrongly correlated materialRaman spectroscopydescription
We measure the Raman scattering spectra of NaTiSi2O6, analyze the vibrational properties, and study the origin of the phase transition in this compound. In this quasi-one-dimensional S = 1/2 system we observe anomalous high-temperature phonon broadenings, and large changes of the phonon energies and line-widths across the phase transition temperature of 210 K. These results, combined with theoretical considerations, indicate that the phonon anomalies originate from an orbital order-disorder type of phase transition. We find that the high temperature dynamical Jahn-Teller phase of NaTiSi2O6 exhibits a spontaneous breaking of translational symmetry into a dimerized, Jahn-Teller distorted, orbital ordered state under the formation of spin valence bonds.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-01-26 | Physical Review B |