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Title: Phase Diffusion in Low-EJ Josephson Junctions at Milli-Kelvin Temperatures
Josephson junctions (JJs) with Josephson energy EJ≲1 K are widely employed as non-linear elements in superconducting circuits for quantum computing operating at milli-Kelvin temperatures. In the qubits with small charging energy EC ( EJ/EC≫1 ), such as the transmon, the incoherent phase slips (IPS) might become the dominant source of dissipation with decreasing EJ. In this work, a systematic study of the IPS in low-EJ JJs at milli-Kelvin temperatures is reported. Strong suppression of the critical (switching) current and a very rapid growth of the zero-bias resistance due to the IPS are observed with decreasing EJ below 1 K. With further improvement of coherence of superconducting qubits, the observed IPS-induced dissipation might limit the performance of qubits based on low-EJ junctions. These results point the way to future improvements of such qubits.  more » « less
Award ID(s):
1838979
PAR ID:
10450292
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Electronics
Volume:
12
Issue:
2
ISSN:
2079-9292
Page Range / eLocation ID:
416
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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