591 citations · 3.4k across the 21 of their papers we have counts for
21 papers
Demonstration of RIP gates in a quantum processor with negligible transverse coupling
Muir Kumph, James Raftery, Aaron Finck +8
Here, we report the experimental demonstration of a novel multi-mode linear bus interferometer (LBI) coupler in a six qubit superconducting quantum processor. A key feature of this…
Spectator Errors in Tunable Coupling Architectures
D. M. Zajac, J. Stehlik, D. L. Underwood +9
The addition of tunable couplers to superconducting quantum architectures offers significant advantages for scaling compared to fixed coupling approaches. In principle, tunable cou…
Quantum crosstalk cancellation for fast entangling gates and improved multi-qubit performance
K. X. Wei, E. Magesan, I. Lauer +14
Quantum computers built with superconducting artificial atoms already stretch the limits of their classical counterparts. While the lowest energy states of these artificial atoms s…
Suppressed crosstalk between two-junction superconducting qubits with mode-selective exchange coupling
A. D. K. Finck, S. Carnevale, D. Klaus +8
Fixed-frequency qubits can suffer from always-on interactions that inhibit independent control. Here, we address this issue by experimentally demonstrating a superconducting archit…
Tunable Coupling Architecture for Fixed-frequency Transmons
J. Stehlik, D. M. Zajac, D. L. Underwood +9
Implementation of high-fidelity two-qubit operations is a key ingredient for scalable quantum error correction. In superconducting qubit architectures tunable buses have been explo…
High-fidelity superconducting quantum processors via laser-annealing of transmon qubits
Eric J. Zhang, Srikanth Srinivasan, Neereja Sundaresan +19
Scaling the number of qubits while maintaining high-fidelity quantum gates remains a key challenge for quantum computing. Presently, superconducting quantum processors with >50-qub…
Demonstration of a High-Fidelity CNOT for Fixed-Frequency Transmons with Engineered ZZ Suppression
A. Kandala, K. X. Wei, S. Srinivasan +6
Improving two-qubit gate performance and suppressing crosstalk are major, but often competing, challenges to achieving scalable quantum computation. In particular, increasing the c…
Demonstration of quantum volume 64 on a superconducting quantum computing system
Petar Jurcevic, Ali Javadi-Abhari, Lev S. Bishop +28
We improve the quality of quantum circuits on superconducting quantum computing systems, as measured by the quantum volume, with a combination of dynamical decoupling, compiler opt…
Tunable Superconducting Qubits with Flux-Independent Coherence
M. D. Hutchings, Jared B. Hertzberg, Yebin Liu +4
We have studied the impact of low-frequency magnetic flux noise upon superconducting transmon qubits with various levels of tunability. We find that qubits with weaker tunability e…
Time-multiplexed amplification in a hybrid-less and coil-less Josephson parametric converter
Baleegh Abdo, Jose M. Chavez-Garcia, Markus Brink +2
Josephson parametric converters (JPCs) are superconducting devices capable of performing nondegenerate, three-wave mixing in the microwave domain without losses. One drawback limit…
Bulk and surface loss in superconducting transmon qubits
Oliver Dial, Douglas T. McClure, Stefano Poletto +4
Decoherence of superconducting transmon qubits is purported to be consistent with surface loss from two-level systems on the substrate surface. Here, we present a study of surface…
Improved superconducting qubit coherence using titanium nitride
J. Chang, M. R. Vissers, A. D. Corcoles +9
We demonstrate enhanced relaxation and dephasing times of transmon qubits, up to ~ 60 μs by fabricating the interdigitated shunting capacitors using titanium nitride (TiN). Compare…
Entanglement of two superconducting qubits in a waveguide cavity via monochromatic two-photon excitation
S. Poletto, Jay M. Gambetta, Seth T. Merkel +9
We report a system where fixed interactions between non-computational levels make bright the otherwise forbidden two-photon 00 --> 11 transition. The system is formed by hand selec…
Efficient measurement of quantum gate error by interleaved randomized benchmarking
Easwar Magesan, Jay M. Gambetta, B. R. Johnson +9
We describe a scalable experimental protocol for obtaining estimates of the error rate of individual quantum computational gates. This protocol, in which random Clifford gates are…
Superconducting qubit in waveguide cavity with coherence time approaching 0.1ms
Chad Rigetti, Stefano Poletto, Jay M. Gambetta +10
We report a superconducting artificial atom with an observed quantum coherence time of T2*=95us and energy relaxation time T1=70us. The system consists of a single Josephson juncti…
Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits
Jerry M. Chow, Jay M. Gambetta, A. D. Corcoles +9
We use quantum process tomography to characterize a full universal set of all-microwave gates on two superconducting single-frequency single-junction transmon qubits. All extracted…
Protecting superconducting qubits from external sources of loss and heat
Antonio D. Córcoles, Jerry M. Chow, Jay M. Gambetta +6
We characterize a superconducting qubit before and after embedding it along with its package in an absorptive medium. We observe a drastic improvement in the effective qubit temper…
A simple all-microwave entangling gate for fixed-frequency superconducting qubits
Jerry M. Chow, A. D. Corcoles, Jay M. Gambetta +8
We demonstrate an all-microwave two-qubit gate on superconducting qubits which are fixed in frequency at optimal bias points. The gate requires no additional subcircuitry and is tu…
High coherence hybrid superconducting qubit
Matthias Steffen, Shwetank Kumar, David P. DiVincenzo +4
We measure the coherence of a new superconducting qubit, the {\em low-impedance flux qubit}, finding s. It is a three-junction flux qubit, but the ratio o…
Readout for Phase Qubits without Josephson Junctions
Matthias Steffen, Shwetank Kumar, David DiVincenzo +4
We present a novel readout scheme for phase qubits which eliminates the read-out SQUID so that the entire qubit and measurement circuitry only requires a single Josephson junction.…
Low-bandwidth control scheme for an oscillator stabilized Josephson qubit
R. H. Koch, J. R. Rozen, G. A. Keefe +4
We introduce a new Josephson junction circuit for which quantum operations are realized by low-bandwidth, nearly adiabatic magnetic-flux pulses. Coupling to the fundamental mode of…