Low-leakage superconducting tunnel junctions with a single-crystal Al 2O3 barrier

S. Oh, K. Cicak, R. McDermott, K. B. Cooper, K. D. Osborn, R. W. Simmonds, M. Steffen, J. M. Martinis, D. P. Pappas

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


We have developed a two-step growth scheme for single-crystal Al 2O3 tunnel barriers. The barriers are epitaxially grown on single-crystal rhenium (Re) base electrodes that are grown epitaxially on a sapphire substrate, while polycrystalline Al is used as the top electrode. We show that by first growing an amorphous aluminium (Al) oxide layer at room temperature and crystallizing it at a high temperature in oxygen environment, a morphologically intact single-crystal Al2O3 layer is obtained. Tunnel junctions fabricated from these trilayers show very low subgap leakage current. This single-crystal Al2O3 junction may open a new venue for coherent quantum devices.

Original languageEnglish (US)
Pages (from-to)1396-1399
Number of pages4
JournalSuperconductor Science and Technology
Issue number10
StatePublished - Oct 1 2005
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Condensed Matter Physics
  • Metals and Alloys
  • Electrical and Electronic Engineering
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Low-leakage superconducting tunnel junctions with a single-crystal Al <sub>2</sub>O<sub>3</sub> barrier'. Together they form a unique fingerprint.

Cite this