TY - JOUR
T1 - Protected josephson rhombus chains
AU - Bell, Matthew T.
AU - Paramanandam, Joshua
AU - Ioffe, Lev B.
AU - Gershenson, Michael E.
PY - 2014/4/25
Y1 - 2014/4/25
N2 - We have studied the low-energy excitations in a minimalistic protected Josephson circuit which contains two basic elements (rhombi) characterized by the π periodicity of the Josephson energy. Novel design of these elements, which reduces their sensitivity to the offset charge fluctuations, has been employed. We have observed that the lifetime T1 of the first excited state of this quantum circuit in the protected regime is increased up to 70μs, a factor of ∼100 longer than that in the unprotected state. The quality factor ω01T1 of this qubit exceeds 106. Our results are in agreement with theoretical expectations; they demonstrate the feasibility of symmetry protection in the rhombus-based qubits fabricated with existing technology.
AB - We have studied the low-energy excitations in a minimalistic protected Josephson circuit which contains two basic elements (rhombi) characterized by the π periodicity of the Josephson energy. Novel design of these elements, which reduces their sensitivity to the offset charge fluctuations, has been employed. We have observed that the lifetime T1 of the first excited state of this quantum circuit in the protected regime is increased up to 70μs, a factor of ∼100 longer than that in the unprotected state. The quality factor ω01T1 of this qubit exceeds 106. Our results are in agreement with theoretical expectations; they demonstrate the feasibility of symmetry protection in the rhombus-based qubits fabricated with existing technology.
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U2 - 10.1103/PhysRevLett.112.167001
DO - 10.1103/PhysRevLett.112.167001
M3 - Article
AN - SCOPUS:84899584613
SN - 0031-9007
VL - 112
JO - Physical Review Letters
JF - Physical Review Letters
IS - 16
M1 - 167001
ER -