1.
Phys Rev Lett
; 85(20): 4353-6, 2000 Nov 13.
Article
in English
| MEDLINE
| ID: mdl-11060636
ABSTRACT
We present elastic and quasielastic neutron scattering measurements characterizing peculiar short-range charge-orbital and spin order in the layered perovskite material La1.5Sr0.5CoO4. We find that below T(c) approximately 750 K holes introduced by Sr doping lose mobility and enter a statically ordered charge glass phase with loosely correlated checkerboard arrangement of empty and occupied d(3z(2)-r(2)) orbitals ( Co3+ and Co2+). The dynamics of the resultant mixed spin system is governed by the anisotropic nature of the crystal-field Hamiltonian and the peculiar exchange pattern produced by the orbital order. It undergoes a spin freezing transition at a much lower temperature, T(s) less, similar30 K.
2.
Phys Rev B Condens Matter
; 53(6): 3428-3435, 1996 Feb 01.
Article
in English
| MEDLINE
| ID: mdl-9983855
3.
Phys Rev B Condens Matter
; 50(21): 15824-15833, 1994 Dec 01.
Article
in English
| MEDLINE
| ID: mdl-9975950