Impedance-based interpretations in 2-dimensional electron gas conduction formed in the LaAlO3/SrxCa1-xTiO3/SrTiO3 system

Chan Rok Park, Seon Young Moon, Da Hee Park, Shin Ik Kim, Seong Keun Kim, Chong-Yun Kang, Seung Hyub Baek, Jung Hae Choi, Jin Sang Kim, Eunsoo Choi, Jin Ha Hwang

Research output: Contribution to journalArticle

Abstract

Frequency-dependent impedance spectroscopy was applied to the 2-dimensioanl conduction transport in the LaAlO3/SrxCa1-xTiO3/SrTiO3 system. The 2-dimensional conduction modifies the electrical/dielectric responses of the LaAlO3/SrxCa1-xTiO3/SrTiO3 depending on the magnitude of the interfacial 2-dimensional resistance. The high conduction of the 2-dimensional electron gas (2DEG) layer can be described using a metallic resistor in series with two parallel RC circuits. However, the high resistance of the 2-dimensional layer drives the composite system from a finite low resistor in parallel with the surrounding dielectrics composed of LaAlO3 and SrTiO3 materials to a dielectric capacitor. This change in the resistance of the 2-dimensional layers modifies the overall impedance enabled by the presence of the interfacial layer due to SrxCa1-xTiO3, which alters the charge transport of the 2-dimensional layer from metallic to semiconducting conduction. A noticeable change is observed in the capacitance Bode plots, indicating highly amplified dielectric constants compared with the pristine SrTiO3 substrates and SrxCa1-xTiO3 with a greater Ca content.

Original languageEnglish
Pages (from-to)131-136
Number of pages6
JournalJournal of Physics and Chemistry of Solids
Volume93
DOIs
Publication statusPublished - 2016 Jun 1
Externally publishedYes

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Keywords

  • Electrical/Dielectric Properties
  • Impedance Spectroscopy
  • Interfacial Property
  • Multilayered Oxide System

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Chemistry(all)
  • Materials Science(all)

Cite this

Park, C. R., Moon, S. Y., Park, D. H., Kim, S. I., Kim, S. K., Kang, C-Y., Baek, S. H., Choi, J. H., Kim, J. S., Choi, E., & Hwang, J. H. (2016). Impedance-based interpretations in 2-dimensional electron gas conduction formed in the LaAlO3/SrxCa1-xTiO3/SrTiO3 system. Journal of Physics and Chemistry of Solids, 93, 131-136. https://doi.org/10.1016/j.jpcs.2016.02.017