532 citations · 4.4k across the 38 of their papers we have counts for
18 papers · 1 filter
Emulating two qubits with a four-level transmon qudit for variational quantum algorithms
Shuxiang Cao, Mustafa Bakr, Giulio Campanaro +7
Using quantum systems with more than two levels, or qudits, can scale the computation space of quantum processors more efficiently than using qubits, which may offer an easier phys…
Efficient characterization of qudit logical gates with gate set tomography using an error-free Virtual-Z-gate model
Shuxiang Cao, Deep Lall, Mustafa Bakr +7
Gate-set tomography (GST) characterizes the process matrix of quantum logic gates, along with measurement and state preparation errors in quantum processors. GST typically requires…
Characterisation of spatial charge sensitivity in a multi-mode superconducting qubit
J. Wills, G. Campanaro, S. Cao +3
Understanding and suppressing sources of decoherence is a leading challenge in building practical quantum computers. In superconducting qubits, low frequency charge noise is a well…
High Coherence in a Tileable 3D Integrated Superconducting Circuit Architecture
Peter A. Spring, Shuxiang Cao, Takahiro Tsunoda +11
We report high qubit coherence as well as low crosstalk and single-qubit gate errors in a superconducting circuit architecture that promises to be tileable to 2D lattices of qubits…
Efficient Hamiltonian programming in qubit arrays with nearest-neighbour couplings
Takahiro Tsunoda, Gaurav Bhole, Stephen A. Jones +2
We consider the problem of selectively controlling couplings in a practical quantum processor with always-on interactions that are diagonal in the computational basis, using sequen…
Rescaling interactions for quantum control
Gaurav Bhole, Takahiro Tsunoda, Peter J. Leek +1
A powerful control method in experimental quantum computing is the use of spin echoes, employed to select a desired term in the system's internal Hamiltonian, while refocusing othe…
Cost function embedding and dataset encoding for machine learning with parameterized quantum circuits
Shuxiang Cao, Leonard Wossnig, Brian Vlastakis +2
Machine learning is seen as a promising application of quantum computation. For near-term noisy intermediate-scale quantum (NISQ) devices, parametrized quantum circuits (PQCs) have…
Modelling Enclosures for Large-Scale Superconducting Quantum Circuits
P. A. Spring, T. Tsunoda, B. Vlastakis +1
Superconducting quantum circuits are typically housed in conducting enclosures in order to control their electromagnetic environment. As devices grow in physical size, the electrom…
Critical slowing down in the bistable regime of circuit quantum electrodynamics
P. Brookes, G. Tancredi, A. D. Patterson +5
We investigate the dynamics of the bistable regime of the generalized Jaynes-Cummings Hamiltonian (GJC), realised by a circuit quantum electrodynamics (cQED) system consisting of a…
Calibration of the cross-resonance two-qubit gate between directly-coupled transmons
A. D. Patterson, J. Rahamim, T. Tsunoda +8
Quantum computation requires the precise control of the evolution of a quantum system, typically through application of discrete quantum logic gates on a set of qubits. Here, we us…
Realization of a Carbon-Nanotube-Based Superconducting Qubit
Matthias Mergenthaler, Ani Nersisyan, Andrew Patterson +6
Hybrid circuit quantum electrodynamics (QED) involves the study of coherent quantum physics in solid state systems via their interactions with superconducting microwave circuits. H…
Optimal control of two qubits via a single cavity drive in circuit quantum electrodynamics
Joseph L. Allen, Robert Kosut, Jaewoo Joo +2
Optimization of the fidelity of control operations is of critical importance in the pursuit of fault-tolerant quantum computation. We apply optimal control techniques to demonstrat…
Circuit quantum acoustodynamics with surface acoustic waves
R. Manenti, A. F. Kockum, A. Patterson +5
The experimental investigation of quantum devices incorporating mechanical resonators has opened up new frontiers in the study of quantum mechanics at a macroscopic level.…
Double-sided coaxial circuit QED with out-of-plane wiring
J. Rahamim, T. Behrle, M. J. Peterer +6
Superconducting circuits are well established as a strong candidate platform for the development of quantum computing. In order to advance to a practically useful level, architectu…
Simultaneous bistability of qubit and resonator in circuit quantum electrodynamics
Th. K. Mavrogordatos, G. Tancredi, M. Elliott +6
We explore the joint activated dynamics exhibited by two quantum degrees of freedom: a cavity mode oscillator which is strongly coupled to a superconducting qubit in the strongly c…
Surface acoustic wave resonators in the quantum regime
R. Manenti, M. J. Peterer, A. Nersisyan +3
We present systematic measurements of the quality factors of surface acoustic wave (SAW) resonators on ST-X quartz in the gigahertz range at a temperature of . W…
Coherence and Decay of Higher Energy Levels of a Superconducting Transmon Qubit
Michael J. Peterer, Samuel J. Bader, Xiaoyue Jin +7
We present measurements of coherence and successive decay dynamics of higher energy levels of a superconducting transmon qubit. By applying consecutive -pulses for each sequenti…
Quantum-to-Classical Transition in Cavity Quantum Electrodynamics
J. M. Fink, L. Steffen, P. Studer +8
The quantum properties of electromagnetic, mechanical or other harmonic oscillators can be revealed by investigating their strong coherent coupling to a single quantum two level sy…