Full Paper

Electronic Effects in Manganite/Insulator Interfaces: Interfacial Enhancement of the Insulating Tunneling Barriers

  1. Lluis Balcells Dr.1,
  2. Llibertat Abad Dr.1,
  3. Humberto Rojas Dr.1,2,
  4. Angel Perez del Pino Dr.1,
  5. Sonia Estrade Dr.3,
  6. Jordi Arbiol Dr.3,4,
  7. Francisca Peiro Dr.3,
  8. Benjamin Martínez Prof.1

Article first published online: 12 FEB 2008

DOI: 10.1002/smll.200700537

Issue

Small

Small

Volume 4, Issue 3, pages 365–371, March 3, 2008

Additional Information

How to Cite

Balcells, L., Abad, L., Rojas, H., Perez del Pino, A., Estrade, S., Arbiol, J., Peiro, F. and Martínez, B. (2008), Electronic Effects in Manganite/Insulator Interfaces: Interfacial Enhancement of the Insulating Tunneling Barriers. Small, 4: 365–371. doi: 10.1002/smll.200700537

Author Information

  1. 1

    Institut de Ciència de Materials de Barcelona, CSIC, Campus universitari de Bellaterra, E- 08193 Bellaterra, Spain, Fax: (+34) 935-805-729

  2. 2

    Escuela de Física, Facultad de Ciencias, Universidad Central de Venezuela, Apdo. 20513, Caracas 1020-A, Venezuela

  3. 3

    EME/CeRMAE/IN2UB, Dept. d'Electrònica, Universitat de Barcelona c/ Marti Franques 1, 08028 Barcelona, Spain

  4. 4

    TEM-MAT, Serveis Cientificotècnics, Universitat de Barcelona c/ Marti Franques 1, 08028 Barcelona,, Spain

Publication History

  1. Issue published online: 26 FEB 2008
  2. Article first published online: 12 FEB 2008
  3. Manuscript Received: 13 JUL 2007

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (689K)

Keywords:

  • conductivity;
  • interfaces;
  • manganites;
  • perovskites;
  • tunneling

Graphical Abstract

Thumbnail image of graphical abstract

Atomic force microscopy in charge-sensing mode allows careful analysis of the transport properties across a manganite/insulator interface (see figure). A nanostructured contact geometry of gold dots is used to facilitate homogeneous current injection. The existence of the interface is found to promote a charge-dragging effect in the topmost layers of the manganite, generating an extra insulating slab of about 1.6-nm thickness.

Abstract

The transport properties across perovskite oxides heterointerfaces are analyzed. Epitaxial La2/3Ca1/3MnO3/SrTiO3 (LCMO/STO) heterostructures with different STO insulating-barrier thicknesses are systematically investigated and their behavior compared with LCMO/metal junctions. Atomic force microscopy (AFM) measurements in current-sensing mode show typical features associated with tunneling conduction. Careful analysis of the I–V curves across LCMO/STO heterointerfaces, using the Simmons model in the intermediate voltage range, clearly shows the existence of an interface-induced enhancement of the tunneling barrier of about 1.6 nm on the LCMO side. These results confirm recent theoretical studies predicting electronic phase segregation and the formation of an orbital-ordered insulating phase at the manganite–insulator interface that is a result of the reduction in the number of charge carriers at the interface.

View Full Article (HTML) Get PDF (689K)