A1 Refereed original research article in a scientific journal

Interfacial Properties of Organic Semiconductor-Inorganic Magnetic Oxide Hybrid Spintronic Systems Fabricated Using Pulsed Laser Deposition




AuthorsSayani Majumdar, Katarzyna Grochowska, Miroslaw Sawczak, Gerard Śliwiński, Hannu Huhtinen, Johnny Dahl, Marjukka Tuominen, Pekka Laukkanen, Himadri S. Majumdar

PublisherAMER CHEMICAL SOC

Publication year2015

JournalACS Applied Materials and Interfaces

Journal name in sourceACS APPLIED MATERIALS & INTERFACES

Journal acronymACS APPL MATER INTER

Volume7

Issue40

First page 22228

Last page22237

Number of pages10

ISSN1944-8244

DOIhttps://doi.org/10.1021/acsami.5b04840


Abstract

We report fabrication of a hybrid organic semiconductor inorganic complex oxide interface of rubrene and La0.67Sr0.33MnO3 (LSMO) for spintronic devices using pulsed laser deposition (PLD) and investigate the interface structure and chemical bonding-dependent magnetic properties. Our results demonstrate that with proper control of growth parameters, thin films of organic semiconductor rubrene can be deposited without any damage to the molecular structure. Rubrene, a widely used organic semiconductor with high charge-carrier mobility and spin diffusion length, when grown as thin films on amorphous and crystalline substrates such as SiO2-glass, indium-tin oxide (ITO), and LSMO by PLD at room temperature and a laser fluence of 0.19 J/cm(2), reveals amorphous structure. The Raman spectra verify the signatures of both A(g) and B-g Raman active modes of rubrene molecules. X-ray reflectivity measurements indicate a well-defined interface formation between surface-treated LSMO and rubrene, whereas X-ray photoelectron spectra indicate the signature of hybridization of the electronic states at this interface. Magnetic measurements show that the ferromagnetic property of the rubrene-LSMO interface improves by >230% compared to the pristine LSMO surface due to this proposed hybridization. Intentional disruption of the direct contact between LSMO and rubrene by insertion of a dielectric AlOx layer results in an observably decreased ferromagnetism. These experimental results demonstrate that by controlling the interface formation between organic semiconductor and half-metallic oxide thin films, it is possible to engineer the interface spin polarization properties. Results also confirm that by using PLD for consecutive growth of different layers, contamination-free interfaces can be obtained, and this finding is significant for the well-controlled and reproducible design of spin-polarized interfaces for future hybrid spintronics devices.




Last updated on 2024-26-11 at 20:44