Fast Logic with Slow Qubits: Microwave-Activated Controlled-Z Gate on Low-Frequency Fluxoniums

@article{Ficheux2020FastLW,
  title={Fast Logic with Slow Qubits: Microwave-Activated Controlled-Z Gate on Low-Frequency Fluxoniums},
  author={Quentin Ficheux and Long B. Nguyen and Aaron Somoroff and Haonan Xiong and K. N. Nesterov and Maxim G. Vavilov and Vladimir E Manucharyan},
  journal={arXiv: Quantum Physics},
  year={2020}
}
We demonstrate a controlled-Z gate between capacitively coupled fluxonium qubits with transition frequencies $72.3~\textrm{MHz}$ and $136.3~\textrm{MHz}$. The gate is activated by a $61.6~\textrm{ns}$ long pulse at the frequency between non-computational transitions $|10\rangle - |20\rangle$ and $|11\rangle - |21\rangle$, during which the qubits complete only $4$ and $8$ Larmor periods, respectively. The measured gate error of $(8\pm1)\times 10^{-3}$ is limited by decoherence in the non… 
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References

SHOWING 1-10 OF 72 REFERENCES
Demonstration of an All-Microwave Controlled-Phase Gate between Far-Detuned Qubits
A challenge in building large-scale superconducting quantum processors is to find the right balance between coherence, qubit addressability, qubit-qubit coupling strength, circuit complexity and the
Efficient Z gates for quantum computing
For superconducting qubits, microwave pulses drive rotations around the Bloch sphere. The phase of these drives can be used to generate zero-duration arbitrary virtual $Z$ gates, which, combined with
Universal Fast-Flux Control of a Coherent, Low-Frequency Qubit
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,
State preparation of a fluxonium qubit with feedback from a custom FPGA-based platform
TLDR
A versatile integrated control and readout instrument for experiments with superconducting quantum bits (qubits), based on a field-programmable gate array (FPGA) platform, that allows for measurement-based, closed-loop feedback operations and improves both the fidelity and the time of the qubit initialization.
Benchmarking the noise sensitivity of different parametric two-qubit gates in a single superconducting quantum computing platform
The possibility to utilize different types of two-qubit gates on a single quantum computing platform adds flexibility in the decomposition of quantum algorithms. A larger hardware-native gate set may
Microwave-activated controlled- Z gate for fixed-frequency fluxonium qubits
The superconducting fluxonium circuit is an artificial atom with a strongly anharmonic spectrum: when biased at a half flux quantum, the lowest qubit transition is an order of magnitude smaller in
Fully microwave-tunable universal gates in superconducting qubits with linear couplings and fixed transition frequencies
A register of quantum bits with fixed transition frequencies and weakly coupled to one another through simple linear circuit elements is an experimentally minimal architecture for a small-scale
Cavity Attenuators for Superconducting Qubits
Dephasing induced by residual thermal photons in the readout resonator is a leading factor limiting the coherence times of qubits in the circuit QED architecture. This residual thermal population, of
Microwave-activated conditional-phase gate for superconducting qubits
We introduce a new entangling gate between two fixed-frequency qubits statically coupled via a microwave resonator bus which combines the following desirable qualities: all-microwave control,
Circuit QED with fluxonium qubits: Theory of the dispersive regime
In circuit QED, protocols for quantum gates and readout of superconducting qubits often rely on the dispersive regime, reached when the qubit-photon detuning {\Delta} is large compared to their
...
...