APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

18 Feb 2013

Volume 102, Issue 7, Articles (07xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 102, 073101 (2013); http://dx.doi.org/10.1063/1.4790646 (4 pages)

V. Reboud, J. Romero-Vivas, P. Lovera, N. Kehagias, T. Kehoe, G. Redmond, and C. M. Sotomayor Torres
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Radiation-suppressed superconducting quantum bit in a planar geometry

Martin Sandberg, Michael R. Vissers, Thomas A. Ohki, Jiansong Gao, José Aumentado, Martin Weides, and David P. Pappas

Appl. Phys. Lett. 102, 072601 (2013); http://dx.doi.org/10.1063/1.4792698 (4 pages)

Online Publication Date: 19 February 2013

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a superconducting transmon qubit circuit design based on large, coplanar capacitor plates and a microstrip resonator. The microstrip geometry, with the ground plane on the back, enhances access to the circuit for state preparation and measurement relative to other designs. The device is fabricated on a silicon substrate using low loss, stoichiometric titanium nitride for the capacitor plates and a single small aluminium/aluminium-oxide/aluminium junction. We observe relaxation and coherence times of 11.7 ± 0.2 μs and 9.6 ± 0.5 μs, respectively, using spin echo. Calculations show that the close proximity of the superconducting back-plane has the added advantage of suppressing the otherwise high radiation loss of the qubit.
Show PACS
85.25.Am Superconducting device characterization, design, and modeling
74.45.+c Proximity effects; Andreev reflection; SN and SNS junctions
74.55.+v Tunneling phenomena: single particle tunneling and STM
61.66.Bi Elemental solids
61.66.Dk Alloys

Current-controllable planar S-(S/F)-S Josephson junction

O. Vávra, W. Pfaff, R. Monaco, M. Aprili, and C. Strunk

Appl. Phys. Lett. 102, 072602 (2013); http://dx.doi.org/10.1063/1.4792213 (3 pages)

Online Publication Date: 20 February 2013

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the experimental realization of a current-controllable lateral S-(S/F)-S Josephson junction based on the inverse proximity effect in the superconductor-ferromagnet bilayer (S/F). The dependence of the critical current on the magnetic field Ic(B) shows a Fresenel-like pattern, which could qualitatively be understood with the theory of Josephson junctions in a magnetic field gradient. The amplitude and the period of the Ic(B) pattern can be controlled by spin-polarized quasiparticles injection into the weak link. The period change suggests controllability of effective area of the Josephson junction. Furthermore, a temperature-induced transition from a weak-link behavior to a strong coupling between the superconducting banks is also observed in these lateral Josephson junctions.
Show PACS
74.50.+r Tunneling phenomena; Josephson effects
74.25.Sv Critical currents
74.45.+c Proximity effects; Andreev reflection; SN and SNS junctions

Penetration depth of MgB2 measured using Josephson junctions and SQUIDs

Daniel Cunnane, Chenggang Zhuang, Ke Chen, X. X. Xi, Jie Yong, and T. R. Lemberger

Appl. Phys. Lett. 102, 072603 (2013); http://dx.doi.org/10.1063/1.4793194 (4 pages)

Online Publication Date: 21 February 2013

Full Text: Read Online (HTML) | Download PDF


See Also: Publisher's Note

Show Abstract
The penetration depth of MgB2 was measured using two methods of different mechanisms. The first method used MgB2 Josephson junctions and the magnetic field dependence of the junction critical current. The second method deduced the penetration depth from the inductance of a MgB2 microstrip used to modulate the voltage of a MgB2 DC SQUID. The two methods showed a consistent value of the low-temperature penetration depth for MgB2 to be about 40 nm. Both the small penetration depth value and its temperature dependence are in agreement with a microscopic theory for MgB2 in the clean limit.
Show PACS
74.50.+r Tunneling phenomena; Josephson effects
74.70.Ad Metals; alloys and binary compounds (including A15, MgB2, etc.)
74.25.Ha Magnetic properties including vortex structures and related phenomena
74.25.Sv Critical currents
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close