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Overlap junctions for superconducting quantum electronics and amplifiers

Journal Article · · Appl.Phys.Lett.
DOI:https://doi.org/10.1063/5.0048621· OSTI ID:1833295
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [2];  [3];  [3];  [4];  [4];  [4];  [4];  [5];  [5];  [6]
  1. NIST, Boulder; Colorado U.
  2. NIST, Boulder; STUK, Helsinki
  3. STUK, Helsinki
  4. Fermilab
  5. Wisconsin U., Madison
  6. NIST, Boulder

Due to their unique properties as lossless, nonlinear circuit elements, Josephson junctions lie at the heart of superconducting quantum information processing. Previously, we demonstrated a two-layer, submicrometer-scale overlap junction fabrication process suitable for qubits with long coherence times. Here, we extend the overlap junction fabrication process to micrometer-scale junctions. This allows us to fabricate other superconducting quantum devices. For example, we demonstrate an overlap junction-based Josephson parametric amplifier that uses only two layers. This efficient fabrication process yields frequency-tunable devices with negligible insertion loss, a gain of ~ 30 dB, and quantum limited noise performance. Compared to other processes, the overlap junction allows for fabrication with minimal infrastructure, high yield, and state-of-the-art device performance.

Research Organization:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP)
DOE Contract Number:
AC02-07CH11359
OSTI ID:
1833295
Report Number(s):
FERMILAB-PUB-21-600-SQMS-TD; arXiv:2005.10908; oai:inspirehep.net:1860914
Journal Information:
Appl.Phys.Lett., Vol. 118, Issue 11
Country of Publication:
United States
Language:
English

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