Muon spin relaxation in mixed perovskite (LaAlO$_3$)$_{x}$(SrAl$_{0.5}$Ta$_{0.5}$O$_3$)$_{1-x}$ with $x\simeq 0.3$

Takashi U. Ito; Wataru Higemoto; Akihiro Koda; Jumpei G. Nakamura; Koichiro Shimomura

doi:10.1007/s10751-024-01866-5

paper

Muon spin relaxation in mixed perovskite (LaAlO $_{3}$ ) $_{x}$ (SrAl $_{0.5}$ Ta $_{0.5}$ O $_{3}$ ) $_{1 - x}$ with $x ≃ 0.3$

arXiv:2405.17371 · doi:10.1007/s10751-024-01866-5

Abstract

We report on muon spin relaxation ( $μ^{+}$ SR) measurements in a mixed perovskite compound, (LaAlO $_{3}$ ) $_{x}$ (SrAl $_{0.5}$ Ta $_{0.5}$ O $_{3}$ ) $_{1 - x}$ with $x ≃ 0.3$ (LSAT), which is widely used as a single-crystalline substrate for thin film deposition. In zero applied field (ZF), muon depolarization due to the distribution of nuclear dipole fields was observed in the temperature range from 4 K to 270 K. Interestingly, $μ^{+}$ SR time spectra in ZF maintained a Gaussian-like feature over the entire range, while the depolarization rate exhibited a monotonic decrease with increasing temperature. This behavior may be attributed to the thermally activated diffusion of muons between a few adjacent sites within a confined space of the angstrom scale, where the motionally averaged local field that each muon experiences can remain non-zero and result in maintaining the Gaussian-like line shape. The spatial distribution of electrostatic potential at lattice interstices evaluated via density functional theory calculations suggests that such a restriction of muon diffusion paths can be caused by the random distribution of cations with different nominal valences in the mixed perovskite lattice.

This preprint has not undergone peer review or any post-submission improvements or corrections. The Version of Record of this article is published in Interactions, and is available online at https://doi.org/10.1007/s10751-024-01866-5

Muon spin relaxation in mixed perovskite (LaAlO3​)x​(SrAl0.5​Ta0.5​O3​)1−x​ with x≃0.3

Abstract

References in corpus (8)

Muon spin relaxation in mixed perovskite (LaAlO $_{3}$ ) $_{x}$ (SrAl $_{0.5}$ Ta $_{0.5}$ O $_{3}$ ) $_{1 - x}$ with $x ≃ 0.3$