Two methods to study inelastic neutron-scattering measurements based on ω_n(q) versus S(q, ω) applied to the magnetic open honeycomb lattice Tb₂Ir₃Ga₉

Journal Article · 25 January 2022 · Journal of Physics. Condensed Matter

DOI: https://doi.org/10.1088/1361-648x/ac49c5 · OSTI ID:1877486

Fishman, Randy S.  ^[1]; Ostrouchov, George  ^[1]; Ye, Feng  ^[1]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

This work describes two methods to fit the inelastic neutron-scattering spectrum S(q, ω) with wavevector q and frequency ω. The common and well-established method extracts the experimental spin-wave branches ω_n(q) from the measured spectra S(q, ω) and then minimizes the difference between the observed and predicted frequencies. When n branches of frequencies are predicted but the measured frequencies overlap to produce only m < n branches, the weighted average of the predicted frequencies must be compared to the observed frequencies. A penalty is then exacted when the width of the predicted frequencies exceeds the width of the observed frequencies. The second method directly compares the measured and predicted intensities S(q, ω) over a grid {q_i, ω_j} in wavevector and frequency space. After subtracting background noise from the observed intensities, the theoretical intensities are scaled by a simple wavevector-dependent function that reflects the instrumental resolution. Furthermore, the advantages and disadvantages of each approach are demonstrated by studying the open honeycomb material Tb₂Ir₃Ga₉.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1877486
• Journal Information: Journal of Physics. Condensed Matter, Journal Name: Journal of Physics. Condensed Matter Journal Issue: 13 Vol. 34; ISSN 0953-8984
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English