Interfacial charge transfer excitation with large optical nonlinearity in manganite heterostructure

[摘要] Interfacial electronic states between LaMnO3 and SrMnO3 have been studied by second-harmonic (SH) spectroscopy. The SH contributions from bulk, surface, and interface were separated by measuring four distinct types of manganite thin films. In the SH spectra, we found a broad peak at 2 eV unique to the LaMnO3/SrMnO3 interface, which was assigned to interfacial charge transfer excitation based on a Hartree-Fock calculation. No metallic phase showed up at the interface. Experimental and theoretical second-order susceptibilities chi((2)) at the interface were estimated to be similar to 10(-6) esu, which is ten times as large as the highest chi((2)) value of BaTiO3.

[发布日期] 2005-12-01

[关键词] 2ND-HARMONIC GENERATION;ODD-PERIOD;SUPERLATTICES