Development and application of a three-dimensional pseudo-Voigt function for muon spin relaxation analysis of weakly magnetic materials.
Rev Sci Instrum
; 95(5)2024 May 01.
Article
en En
| MEDLINE
| ID: mdl-38717269
ABSTRACT
We present a three-dimensional pseudo-Voigt function to analyze muon spin relaxation (µSR) in weakly magnetic materials. Our approach approximates the Voigt function by superimposing Gaussian and Lorentzian functions using a one-dimensional method proposed by Di Rocco and Cruzado [Acta Phys. Pol., A 122, 666 (2012)]. We derive the peak of the Voigt function analytically and express the Half Width at Half Maximum (HWHM) of the Voigt function as a function of the HWHMs of the Gaussian and Lorentzian functions. We compare the pseudo-Voigt function to the exact Voigt function and find a maximum normalized discrepancy of â¼20% at the tail of the distribution function, depending on the ratio of Lorentzian to Gaussian HWHMs and internal magnetic field. We apply the derived three-dimensional pseudo-Voigt function to calculate µSR functions for zero- and longitudinal-field experiments and use them to fit µSR time spectra of La2-xSrxCuO4 with 2.4% Sr, employing a strong collision model with the static-based pseudo-Voigt muon spin relaxation function as the initial condition. Our results show that the Gaussian- and Lorentzian-fitted parameters and fluctuation rate are in good agreement with results from the exact Voigt function for a temperature range of 30-200 K, with the deviation of Gaussian and Lorentzian width parameters reaching â¼0.15 G below 30 K.
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Base de datos:
MEDLINE
Idioma:
En
Revista:
Rev Sci Instrum
/
Rev. sci. instrum
/
Review of scientific instruments
Año:
2024
Tipo del documento:
Article
País de afiliación:
Indonesia