Electron spin resonance across the charge-ordering transition in YBaMn 2 O 6

摘要: We investigated the metal-ordered manganite system ${\text{YBaMn}}_{2}{\text{O}}_{6}$ using electron spin resonance (ESR) in paramagnetic regime across charge ordering and structural phase transition at ${T}_{\text{CO}}=480\text{ }\text{K}$ ${T}_{t}=520\text{ }\text{K}$, respectively. All ESR parameters exhibit jumplike changes ${T}_{t}$ while ${T}_{\text{CO}}$ manifests itself only as a weak broad anomaly. Above susceptibility is reduced with respect to dc susceptibility, indicating that ${t}_{2g}$-core spins of Mn ions contribute absorption. The contribution ${e}_{g}$ suppressed by time scale polaronic hopping process electrons. linewidth this reminiscent Korringa-type relaxation behavior. In picture properties below are dominated slowing down process. fluctuations persist temperature ${T}^{\ensuremath{\ast}}\ensuremath{\approx}410\text{ which can be described charge-ordered assembly ${\text{Mn}}^{3+}$ ${\text{Mn}}^{4+}$ spins.