Dynamic lattice distortions in Sr₂RuO₄: microscopic studies by perturbed angular correlation spectroscopy andab initiocalculations

Abstract

Applying time differential perturbed angular correlation (TDPAC) spectroscopy and ab initio calculations, we have investigated possible lattice instabilities in Sr(2)RuO(4) by studying the electric quadrupole interaction of a (111)Cd probe at the Ru site. We find evidence for a dynamic lattice distortion, revealed from the observations of: (i) a rapidly fluctuating electric-field gradient (EFG) tensor showing non-Arrhenius relaxation, (ii) an anomalous temperature dependence of the quadrupole interaction frequency, and (iii) a monotonic increase of the EFG asymmetry (η) below 300 K. We argue that the observed dynamic lattice distortion is caused by strong spin fluctuations associated with the inherent magnetic instability in Sr(2)RuO(4).

Dynamic off-centering of Cr3+ions and short-range magneto-electric clusters in CdCr2S4Oliveira1, Pereira2, Lopes3 et al. 2012Phys. Rev. B271170View full textAdd to dashboardCite

“…At T < 200 K, the R(t) and Ft plots are visibly altered, particularly between 119 K and 92 K where R(t) becomes increasingly damped as the temperature decreases. This increased damping of the R(t) spectra is attributed to timedependent interactions 24 , i.e., EFG fluctuations within the PAC timescale (1 µs> τ > 1 ns; τ -characteristic fluctuation time). 25 This effect can be modeled by including a dynamic attenuation parameter (λ) in the standard static fit function 25 (as introduced in Eq.…”

Local inhomogeneous state in multiferroic SmCrO3

“…Revealing the density and asymmetry of the local charge distribution, the EFG allows one to infer about the atomic and electronic environment of the probe nuclei. PAC has given proof of being a valuable technique to study local anomalies in complex oxides 37,[40][41][42] that we now apply to study SmCrO 3 .…”

Experimental TDPAC and Theoretical DFT Study of Structural, Electronic, and Hyperfine Properties in (111In → )111Cd-Doped SnO2 Semiconductor: Ab Initio Modeling of the Electron-Capture-Decay After-Effects Phenomenon

“…In the last years, in condensed-matter physics, structural, electronic, and magnetic properties in pure and doped systems have been carefully studied at the atomic scale confronting results from hyperfine experimental techniques with reliable all-electron (AE) ab initio predictions in the framework of the density functional theory (DFT). − In particular, the subnanoscopic environment of impurities or native atoms in solids can be studied employing the time-differential perturbed γ–γ angular-correlation (TDPAC) spectroscopy. This technique provides a very precise characterization of the electric-field-gradient (EFG) tensor at diluted (ppm) radioactive probe atoms.…”