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arXiv · 2106.02360

Neutron diffraction of field-induced magnon condensation in the spin-dimerized antiferromagnet Sr$_{3}$Cr$_{2}$O$_{8}$

Alsu Gazizulina·Diana Lucia Quintero-Castro·Zhe Wang·Fabienne Duc·Frederic Bourdarot·Karel Prokes·Wolfgang Schmidt·Ramzy Daou·Sergei Zherlitsyn·Nazmul Islam·Nils Henrik Kolnes·Abhijit Bhat Kademane·Andreas Schilling·Bella Lake
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Abstract

In this work, we investigate the evolution and settling of magnon condensation in the spin-1/2 dimer system Sr$_{3}$Cr$_{2}$O$_{8}$ using a combination of magnetostriction in pulsed fields and inelastic neutron scattering in a continuous magnetic field. The magnetic structure in the Bose-Einstein condensation (BEC) phase was probed by neutron diffraction in pulsed magnetic fields up to 39~T. The magnetic structure in this phase was confirmed to be an XY-antiferromagnetic structure validated by irreducible representational analysis. The magnetic phase diagram as a function of an applied magnetic field for this system is presented. Furthermore, zero-field neutron diffraction results indicate that dimerization plays an important role in stabilizing the low-temperature crystal structure.

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Alsu Gazizulina, Diana Lucia Quintero-Castro, Zhe Wang, Fabienne Duc, Frederic Bourdarot, Karel Prokes, Wolfgang Schmidt, Ramzy Daou, Sergei Zherlitsyn, Nazmul Islam, Nils Henrik Kolnes, Abhijit Bhat Kademane, Andreas Schilling, Bella Lake. 2021-06-04. Neutron diffraction of field-induced magnon condensation in the spin-dimerized antiferromagnet Sr$_{3}$Cr$_{2}$O$_{8}$. https://doi.org/10.1103/physrevb.104.064430

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