Magnetic phase diagram of the quantum spin chain compound SrCo₂V₂O₈ : A single-crystal neutron diffraction study

Summary, in English

We explore magnetic order in the quantum spin chain compound SrCo₂V₂O₈ up to 14.9 T and down to 50 mK, using single-crystal neutron diffraction. Upon cooling in zero-field, commensurate antiferromagnetic (C-AFM) order with modulation vector=(0, 0, 1) develops below T _N≃5.0K. Applying an external magnetic field (H∥c axis) destabilizes this C-AFM order, leading to an order-disorder transition between T _N and ∼1.5 K. Below 1.5 K, a commensurate to incommensurate (IC-AFM) transition occurs at 3.9 T, above which the magnetic reflections can be indexed by=(0, 0, 1 ±δl). The incommensurability δl scales monotonically with H until the IC-AFM order disappears around 7.0 T. Magnetic reflections modulated by emerge again at higher fields. While the characters of the C-AFM, IC-AFM and the emergent AFM order in SrCo₂V₂O₈ appear to fit the descriptions of the Néel, longitudinal spin density wave and transverse AFM order observed in the related compound BaCo₂V₂O₈, our results also reveal several unique signatures that are not present in the latter, highlighting the inadequacy of mean-field theory in addressing the complex magnetic order in systems of this class.

• Author: L. Shen; O. Zaharko; Jonas Okkels Birk; E. Jellyman; Z. He; E. Blackburn
• Department/s: Synchrotron Radiation Research
• Publishing year: 2019-07-03
• Language: English
• Publication/Series: New Journal of Physics
• Volume: 21
• Issue: 7
• Full text: - 2 MB; Download statistics
• Links: http://dx.doi.org/10.1088/1367-2630/ab2b7a
• Document type: Journal article
• Publisher: IOP Publishing
• Topic: Condensed Matter Physics (including Material Physics, Nano Physics)
• Keywords: Low dimensional quantum magnetism; Magnetic-field-induced phase transitions; Quantum criticality
• Status: Published
• Project: Accessing high pressure and low temperature states of exotic magnetism
• ISBN/ISSN/Other: ISSN: 1367-2630