Structural-modulation-driven low-temperature glassy behavior in SrRuO3

Abstract

We present a critical investigation on the structural, magnetic, and magnetotransport properties of two sets of polycrystalline SrRuO 3 samples with uniquely defined ferromagnetic transition temperatures. The ac magnetic susceptibility study exhibits the remarkable memory effect, a distinct characteristic of glassy behavior, at low temperatures. The transport study suggests a crossover from Fermi-liquid to non-Fermi-liquid behavior. Most strikingly, the temperature-dependent magnetoresistance exhibits two distinct dips (one around ferromagnetic ordering temperature and the other around 50 K), resembling a double-well potential in appearance. In addition, the temperature-dependent coercive field shows a plateau around 50 K. An attempt has been made to employ neutron diffraction to understand the genesis of such unusual low-temperature magnetic features. From the neutron-diffraction study, we find the evidence for changes in the unit-cell lattice parameters around 60 K and, thus, believe that the low-temperature anomalous magnetic response is closely intertwined to lattice-parameter change.

Oxygen deficiency and cooling field driven vertical hysteretic shift in epitaxial SrRuO3/SrTiO3 heterostructures

“…Such disparity in b is probably caused by dissimilar defects, domains, and lattice distortions. 23 These findings explicitly prove that oxygen defect tunable magnetic mTorr, as measured at T ¼ 10, 50, 100, and 140 K after being cooled from T ¼ 300 K with and without the application of H CF ¼ 61 T, respectively. The inset in Fig.…”

“…The observation of such a significant oxygen deficiency-induced evolution of T C (DT C $ 95 K) in SRO films is believed to be unprecedented and demonstrates the effectiveness of oxygen deficiency-manipulation of lattice distortion and electronic structure. Similar to the findings in the SRO bulk and thin films, 22,23 the magnetization data near T C can be fitted using the scaling law M / ðT C À TÞ b [see the red line], where M is the spontaneous magnetization and b is the critical exponent. The b value of the SRO film for P O 2 ¼150 mTorr is $0.46, close to that ($0.5) of the SRO single crystal, 24 and thus can be reasonably explained on account of the mean field model.…”

Electronic properties in itinerant ferromagnet SrRu1−x Ti x O3

“…1 shows the calculated negative MR with pronounced dips around T c and at low temperature ∼ 50 K which is also matches with reported studies. [27,28] The ρ(T ) data for SrRu 1−x Ti x O 3 series are shown in Fig. 2a and Fig.…”

High stability of electro-transport and magnetism against the A-site cation disorder in SrRuO3

“…We see a clear separation of the M ( T ) curves under the ZFC and FC modes with a small cusp right below T c for all the samples including pure SRO. Although SRO is often seen as a ferromagnetic metal, such a feature of ZFC-FC separation in polycrystalline bulk SRO, thin film SRO, and even single crystal SRO, was reported in earlier works 75 76 77 . Indeed, the FC mode measured M ( T ) data do show ferromagnetic transition around T c , but the clear separation in M ( T ) curve between the ZFC and FC modes is also a well-established feature.…”