Details

Autor(en) / Beteiligte

• Biffin, A
• Rüegg, Ch
• Embs, J
• Guidi, T
• Cheptiakov, D
• Loidl, A
• Tsurkan, V
• Coldea, R

Titel

Magnetic Field Dependence of Excitations Near Spin-Orbital Quantum Criticality

Ist Teil von

• Physical review letters, 2017-02, Vol.118 (6), p.067205-067205, Article 067205

Ort / Verlag

United States

Erscheinungsjahr

2017

Link zum Volltext

Quelle

PROLA - Physical Review Online Archive

Beschreibungen/Notizen

• The spinel FeSc_{2}S_{4} has been proposed to realize a near-critical spin-orbital singlet (SOS) state, where entangled spin and orbital moments fluctuate in a global singlet state on the verge of spin and orbital order. Here we report powder inelastic neutron scattering measurements that observe the full bandwidth of magnetic excitations and we find that spin-orbital triplon excitations of an SOS state can capture well key aspects of the spectrum in both zero and applied magnetic fields up to 8.5 T. The observed shift of low-energy spectral weight to higher energies upon increasing applied field is naturally explained by the entangled spin-orbital character of the magnetic states, a behavior that is in strong contrast to spin-only singlet ground state systems, where the spin gap decreases upon increasing applied field.