Interfacial properties of organic semiconductor-inorganic magnetic oxide hybrid spintronic systems fabricated using pulsed laser deposition

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

Research output: Contribution to journalArticleScientificpeer-review

11 Citations (Scopus)

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/cm2, reveals amorphous structure. The Raman spectra verify the signatures of both Ag and Bg 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.
Original languageEnglish
Pages (from-to)22228-22237
JournalACS Applied Materials & Interfaces
Volume7
Issue number40
DOIs
Publication statusPublished - 2015
MoE publication typeA1 Journal article-refereed

Keywords

  • pulsed laser deposition
  • organic spintronics
  • organic semiconductor thin films
  • magnetic properties
  • hybrid interface

Fingerprint Dive into the research topics of 'Interfacial properties of organic semiconductor-inorganic magnetic oxide hybrid spintronic systems fabricated using pulsed laser deposition'. Together they form a unique fingerprint.

  • Cite this