# High-Coherence Fluxonium Qubit

@article{Nguyen2019HighCoherenceFQ, title={High-Coherence Fluxonium Qubit}, author={Long B. Nguyen and Yen-Hsiang Lin and Aaron Somoroff and Raymond A. Mencia and Nicholas Grabon and Vladimir E Manucharyan}, journal={Physical Review X}, year={2019} }

We report superconducting fluxonium qubits with coherence times largely limited by energy relaxation and reproducibly satisfying T2 > 100 microseconds (T2 > 300 microseconds in one device). Moreover, given the state of the art values of the surface loss tangent and the 1/f flux noise amplitude, coherence can be further improved beyond 1 millisecond. Our results violate a common viewpoint that the number of Josephson junctions in a superconducting circuit -- over 100 here -- must be minimized…

## 100 Citations

Millisecond coherence in a superconducting qubit

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The \textit{heavy-fluxonium} circuit is a promising building block for superconducting quantum processors due to its long relaxation and dephasing time at the half-flux frustration point. However,…

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We propose a family of microwave-activated entangling gates on two capacitively coupled fluxonium qubits. A microwave pulse applied to either qubit at a frequency near the half-frequency of the…

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