• Hadermann, Joke
• Batuk, Maria
• Palgrave, Robert G.
• Darling, George R.
• Tan, Haiyan
• Mcmitchell, Sean R. C.
• Verbeeck, Jo
• Rosseinsky, Matthew J.
• Tian, He
• Dyer, Matthew S.
• Borisov, Pavel
• Claridge, John B.

Abstract

Pulsed laser deposition has been used to artificially construct the n = 3 Ruddlesden–Popper structure La2Sr2Mn3O10 in epitaxial thin film form by sequentially layering La1–xSrxMnO3 and SrO unit cells aided by in situ reflection high energy electron diffraction monitoring. The interval deposition technique was used to promote two-dimensional SrO growth. X-ray diffraction and cross-sectional transmission electron microscopy indicated that the trilayer structure had been formed. A site ordering was found to differ from that expected thermodynamically, with the smaller Sr2+ predominantly on the R site due to kinetic trapping of the deposited cation sequence. A dependence of the out-of-plane lattice parameter on growth pressure was interpreted as changing the oxygen content of the films. Magnetic and transport measurements on fully oxygenated films indicated a frustrated magnetic ground state characterized as a spin glass-like magnetic phase with the glass temperature Tg ≈ 34 K. The magnetic frustration has a clear in-plane (ab) magnetic anisotropy, which is maintained up to temperatures of 150 K. Density functional theory calculations suggest competing antiferromagnetic and ferromagnetic long-range orders, which are proposed as the origin of the low-temperature glassy state.

Topics

• density
• impedance spectroscopy
• phase
• x-ray diffraction
• theory
• thin film
• Oxygen
• glass
• glass
• layered
• transmission electron microscopy
• thermogravimetry
• density functional theory
• two-dimensional
• pulsed laser deposition
• oxygen content
• high energy electron diffraction