11 papers
Low-energy spectrum of double-junction superconducting circuits in the Born-Oppenheimer approximation
Leo Uhre Jakobsen, Ksenia Shagalov, David Feldstein-Bofill +3
The superconductor-insulator-superconductor Josephson junction is the fundamental nonlinear element of superconducting circuits. Connecting two junctions in series gives rise to hi…
Observation of coherent flux-charge interaction in a gate-tunable fluxonium
Brian D. Isakov, Shikhar Singh, Adrian Parra-Rodriguez +7
Interactions that mix conjugate variables, such as the flux through a circuit element and the charge across it, lie outside the reach of the elementary couplings of superconducting…
Learning Lindblad Dynamics of a Superconducting Quantum Processor
Johann Bock Severin, Malthe A. Marciniak, Rune Thinggaard Birke +13
Accurate models of quantum processors are essential for understanding, calibrating, and improving their performance. In practice, model construction must balance physical detail ag…
Junction-Intrinsic Dissipation in Hybrid Superconductor-Semiconductor Gatemon Qubits
Zhenhai Sun, David Feldstein-Bofill, Ksenia Shagalov +10
Superconducting transmon qubits based on hybrid superconductor-semiconductor Josephson junctions (gatemons) offer gate tunability, but their relaxation times remain well below thos…
Demonstrating and Benchmarking Classical Shadows for Lindblad Tomography
Rune Thinggaard Birke, Johann Bock Severin, Malthe A. Marciniak +15
Spurious couplings and decoherence degrade the performance of solid-state quantum processors, demanding careful design, calibration, and mitigation protocols. These strategies ofte…
Real-time adaptive tracking of fluctuating relaxation rates in superconducting qubits
Fabrizio Berritta, Jacob Benestad, Jan A. Krzywda +17
The fidelity of operations on a solid-state quantum processor is fundamentally bounded by environmental decoherence. Characterizing environmental fluctuations is challenging becaus…