2010/03/10 by Indu Dhiman, Thierry Strässle, L. Keller +2
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Ambient pressure #Antiferromagnetism #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Geology #Magnetic and transport properties of perovskites and related materials #Magnetic moment #Materials science #Neutron diffraction #Phase (matter) #Physics #Quantum mechanics #Rare-earth and actinide compounds #Thermodynamics #Type (biology) #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.81.104424
9 pages, 6 figures, 1 table, To appear in Physical Review B
arxiv created 2010/03/10 · openalex publication_date 2010/03/30 · arxiv updated 2015/05/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The effect of high pressure (0--8 GPa) on the magnetic structure of polycrystalline samples of La0.5Ca_0.5\ensuremath-xSrxMnO3 (0.1\ensuremath≤x\ensuremath≤0.4) manganites at 5 K is investigated using neutron-diffraction technique. Application of pressure is found to modify the previously reported magnetic structure, observed under ambient conditions, in these compounds [I. Dhiman et al., Phys. Rev. B 77, 094440 (2008)]. In x=0.1 composition, at 4.6(2) GPa and beyond, A-type antiferromagnetic structure is found to coexist with charge-exchange (CE)-type antiferromagnetic phase, observed at ambient pressure, with TN\ensuremath∼150 K. For x=0.3 sample, as a function of pressure the CE-type phase is fully suppressed at 2.3(1) GPa and A-type antiferromagnetic phase is favored. Further Sr doping at x=0.4, the A-type antiferromagnetic phase is observed at ambient pressure and for T<TN (\ensuremath∼250 K). This phase is retained in the studied pressure range. However, the magnetic moment progressively reduces with increasing pressure, indicating the suppression of A-type antiferromagnetic phase. The present study brings out the fragile nature of the CE-type antiferromagnetic state in half-doped manganites as a function of pressure and disorder \ensuremathσ2. We observe that pressure required for destabilizing the CE-type antiferromagnetic state is reduced with increasing disorder \ensuremathσ2. External pressure and changing A-site ionic radii have analogous effect on the magnetic structure.