By Topic

Low-loss epitaxial NbN/MgO/NbN trilayers for THz applications

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
A. Kawakami ; Commun. Res. Lab., Kansai Adv. Res. Center, Kobe, Japan ; Zhen Wang ; S. Miki

To improve the performance of Josephson oscillators and SIS mixers over 700 GHz, we have developed a fabrication process to grow epitaxial NbN/MgO/NbN trilayers by reactive dc-sputtering. Trilayers were fabricated on a single-crystal MgO substrate at ambient temperature. NbN and MgO films were deposited by reactive dc-sputtering with an Nb and Mg target, respectively. The MgO inter-layer thickness was changed up to 480 nm, but, TC and 20-K resistivity of the NbN upper-layer showed no remarkable dependency and they were 15.7 K and about 60 μΩcm, respectively. To evaluate the RF performance of the epitaxial NbN films, we fabricated Josephson junctions with a microstrip resonator constructed from an epitaxial NbN/MgO/NbN trilayer. The I-V characteristics of the junction exhibited resonance steps up to 2.5 mV, which suggests that the epitaxial NbN films have low loss up to 1.2 THz

Published in:

IEEE Transactions on Applied Superconductivity  (Volume:11 ,  Issue: 1 )