π-Loops with ds josephson junctions

M. I. Faley* (Corresponding Author), P. Reith, V. S. Stolyarov, I. A. Golovchanskiy, A. A. Golubov, H. Hilgenkamp, R. E. Dunin-Borkowski

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

1 Downloads (Pure)

Abstract

We fabricated Josephson junctions (JJs) between the d-wave superconductor (SC) YBa 2 Cu 3 O 7 -x (YBCO) and the s-wave SC Nb (ds-JJs) on graphoepitaxially buffered MgO substrates, studied ds-JJs at temperatures down to 30 mK and employed these JJs in π-loops. Current-voltage characteristics of ds-JJs oriented along the [100] axis of YBCO exhibited up to a factor of 200 higher critical current densities than ds-JJs oriented along the [110] axis of YBCO. The critical current I c and the I c R n product of [100]-oriented 3 μm wide ds-JJs are ∼70 μA and ∼200 μV, respectively, at 4.2 K. Rectangular arrays of up to 40 000 π-loops based on such ds-JJs were investigated using a low temperature scanning superconducting quantum interference device (SQUID) microscope. We observed ordering of spontaneously generated half integer magnetic flux quanta in the π-loops correlated with minute spurious background magnetic fields, as well as with configurations and mutual coupling of the π-loops. We manipulated the magnetic states of the π-loops by the local application of magnetic fields using nearby planar coils. This paper paves the way for the use of π-loops in computations that are based on annealing processes.

Original languageEnglish
Article number8606963
JournalIEEE transactions on applied superconductivity
Volume29
Issue number5
Early online date10 Jan 2010
DOIs
Publication statusPublished - 1 Aug 2019

Fingerprint

Josephson junctions
Superconducting materials
Magnetic fields
Critical currents
SQUIDs
Magnetic flux
Current voltage characteristics
Microscopes
Annealing
Scanning
Temperature
Substrates
critical current
magnetic fields
integers
magnetic flux
coils
microscopes
current density
interference

Keywords

  • High-temperature superconductors
  • Josephson junctions
  • quantum computing
  • scanning probe microscopy
  • superconducting quantum interference devices (SQUIDs)

Cite this

Faley, M. I., Reith, P., Stolyarov, V. S., Golovchanskiy, I. A., Golubov, A. A., Hilgenkamp, H., & Dunin-Borkowski, R. E. (2019). π-Loops with ds josephson junctions. IEEE transactions on applied superconductivity, 29(5), [8606963]. https://doi.org/10.1109/TASC.2019.2892078
Faley, M. I. ; Reith, P. ; Stolyarov, V. S. ; Golovchanskiy, I. A. ; Golubov, A. A. ; Hilgenkamp, H. ; Dunin-Borkowski, R. E. / π-Loops with ds josephson junctions. In: IEEE transactions on applied superconductivity. 2019 ; Vol. 29, No. 5.
@article{6d90a5910d054afb9af467a36e4f30e4,
title = "π-Loops with ds josephson junctions",
abstract = "We fabricated Josephson junctions (JJs) between the d-wave superconductor (SC) YBa 2 Cu 3 O 7 -x (YBCO) and the s-wave SC Nb (ds-JJs) on graphoepitaxially buffered MgO substrates, studied ds-JJs at temperatures down to 30 mK and employed these JJs in π-loops. Current-voltage characteristics of ds-JJs oriented along the [100] axis of YBCO exhibited up to a factor of 200 higher critical current densities than ds-JJs oriented along the [110] axis of YBCO. The critical current I c and the I c R n product of [100]-oriented 3 μm wide ds-JJs are ∼70 μA and ∼200 μV, respectively, at 4.2 K. Rectangular arrays of up to 40 000 π-loops based on such ds-JJs were investigated using a low temperature scanning superconducting quantum interference device (SQUID) microscope. We observed ordering of spontaneously generated half integer magnetic flux quanta in the π-loops correlated with minute spurious background magnetic fields, as well as with configurations and mutual coupling of the π-loops. We manipulated the magnetic states of the π-loops by the local application of magnetic fields using nearby planar coils. This paper paves the way for the use of π-loops in computations that are based on annealing processes.",
keywords = "High-temperature superconductors, Josephson junctions, quantum computing, scanning probe microscopy, superconducting quantum interference devices (SQUIDs)",
author = "Faley, {M. I.} and P. Reith and Stolyarov, {V. S.} and Golovchanskiy, {I. A.} and Golubov, {A. A.} and H. Hilgenkamp and Dunin-Borkowski, {R. E.}",
year = "2019",
month = "8",
day = "1",
doi = "10.1109/TASC.2019.2892078",
language = "English",
volume = "29",
journal = "IEEE transactions on applied superconductivity",
issn = "1051-8223",
publisher = "IEEE",
number = "5",

}

Faley, MI, Reith, P, Stolyarov, VS, Golovchanskiy, IA, Golubov, AA, Hilgenkamp, H & Dunin-Borkowski, RE 2019, 'π-Loops with ds josephson junctions', IEEE transactions on applied superconductivity, vol. 29, no. 5, 8606963. https://doi.org/10.1109/TASC.2019.2892078

π-Loops with ds josephson junctions. / Faley, M. I. (Corresponding Author); Reith, P.; Stolyarov, V. S.; Golovchanskiy, I. A.; Golubov, A. A.; Hilgenkamp, H.; Dunin-Borkowski, R. E.

In: IEEE transactions on applied superconductivity, Vol. 29, No. 5, 8606963, 01.08.2019.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - π-Loops with ds josephson junctions

AU - Faley, M. I.

AU - Reith, P.

AU - Stolyarov, V. S.

AU - Golovchanskiy, I. A.

AU - Golubov, A. A.

AU - Hilgenkamp, H.

AU - Dunin-Borkowski, R. E.

PY - 2019/8/1

Y1 - 2019/8/1

N2 - We fabricated Josephson junctions (JJs) between the d-wave superconductor (SC) YBa 2 Cu 3 O 7 -x (YBCO) and the s-wave SC Nb (ds-JJs) on graphoepitaxially buffered MgO substrates, studied ds-JJs at temperatures down to 30 mK and employed these JJs in π-loops. Current-voltage characteristics of ds-JJs oriented along the [100] axis of YBCO exhibited up to a factor of 200 higher critical current densities than ds-JJs oriented along the [110] axis of YBCO. The critical current I c and the I c R n product of [100]-oriented 3 μm wide ds-JJs are ∼70 μA and ∼200 μV, respectively, at 4.2 K. Rectangular arrays of up to 40 000 π-loops based on such ds-JJs were investigated using a low temperature scanning superconducting quantum interference device (SQUID) microscope. We observed ordering of spontaneously generated half integer magnetic flux quanta in the π-loops correlated with minute spurious background magnetic fields, as well as with configurations and mutual coupling of the π-loops. We manipulated the magnetic states of the π-loops by the local application of magnetic fields using nearby planar coils. This paper paves the way for the use of π-loops in computations that are based on annealing processes.

AB - We fabricated Josephson junctions (JJs) between the d-wave superconductor (SC) YBa 2 Cu 3 O 7 -x (YBCO) and the s-wave SC Nb (ds-JJs) on graphoepitaxially buffered MgO substrates, studied ds-JJs at temperatures down to 30 mK and employed these JJs in π-loops. Current-voltage characteristics of ds-JJs oriented along the [100] axis of YBCO exhibited up to a factor of 200 higher critical current densities than ds-JJs oriented along the [110] axis of YBCO. The critical current I c and the I c R n product of [100]-oriented 3 μm wide ds-JJs are ∼70 μA and ∼200 μV, respectively, at 4.2 K. Rectangular arrays of up to 40 000 π-loops based on such ds-JJs were investigated using a low temperature scanning superconducting quantum interference device (SQUID) microscope. We observed ordering of spontaneously generated half integer magnetic flux quanta in the π-loops correlated with minute spurious background magnetic fields, as well as with configurations and mutual coupling of the π-loops. We manipulated the magnetic states of the π-loops by the local application of magnetic fields using nearby planar coils. This paper paves the way for the use of π-loops in computations that are based on annealing processes.

KW - High-temperature superconductors

KW - Josephson junctions

KW - quantum computing

KW - scanning probe microscopy

KW - superconducting quantum interference devices (SQUIDs)

UR - http://www.scopus.com/inward/record.url?scp=85061107013&partnerID=8YFLogxK

U2 - 10.1109/TASC.2019.2892078

DO - 10.1109/TASC.2019.2892078

M3 - Article

AN - SCOPUS:85061107013

VL - 29

JO - IEEE transactions on applied superconductivity

JF - IEEE transactions on applied superconductivity

SN - 1051-8223

IS - 5

M1 - 8606963

ER -