96 citations · 426 across the 16 of their papers we have counts for
17 papers
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…
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…
Mitigating transients in flux-control signals in a superconducting quantum processor
Anuj Aggarwal, Jorge Fernández-Pendás, Tahereh Abad +12
Flux-tunable qubits and couplers are common components in superconducting quantum processors. However, dynamically controlling these elements via current pulses poses challenges du…
Fast unconditional reset and leakage reduction in fixed-frequency transmon qubits
Liangyu Chen, Simon Pettersson Fors, Zixian Yan +24
The realization of fault-tolerant quantum computing requires the execution of quantum error-correction (QEC) schemes, to mitigate the fragile nature of qubits. In this context, to…
Signal crosstalk in a flip-chip quantum processor
Sandoko Kosen, Hang-Xi Li, Marcus Rommel +15
Quantum processors require a signal-delivery architecture with high addressability (low crosstalk) to ensure high performance already at the scale of dozens of qubits. Signal cross…
Fast generation of Schrödinger cat states in a Kerr-tunable superconducting resonator
X. L. He, Yong Lu, D. Q. Bao +7
Schrödinger cat states, quantum superpositions of macroscopically distinct classical states, are an important resource for quantum communication, quantum metrology and quantum comp…
Modeling and Harmonic Balance Analysis of Parametric Amplifiers for Qubit Read-out
Daryoush Shiri, Hampus Renberg Nilsson, Pavan Telluri +4
Predicting the performance of traveling-wave parametric amplifiers (TWPAs) based on nonlinear elements like superconducting Josephson junctions (JJs) is vital for qubit read-out in…
Mitigation of frequency collisions in superconducting quantum processors
Amr Osman, Jorge Fernàndez-Pendàs, Christopher Warren +6
The reproducibility of qubit parameters is a challenge for scaling up superconducting quantum processors. Signal crosstalk imposes constraints on the frequency separation between n…
Three-wave mixing traveling-wave parametric amplifier with periodic variation of the circuit parameters
Anita Fadavi Roudsari, Daryoush Shiri, Hampus Renberg Nilsson +8
We report the implementation of a near-quantum-limited, traveling-wave parametric amplifier that uses three-wave mixing (3WM). To favor amplification by 3WM, we use the superconduc…
A high gain travelling-wave parametric amplifier based on three-wave mixing
Hampus Renberg Nilsson, Anita Fadavi Roudsari, Daryoush Shiri +2
We extend the theory for a Josephson junction travelling wave parametric amplifier (TWPA) operating in the three-wave mixing regime and we propose a scheme for achieving high gain.…
Qubit-compatible substrates with superconducting through-silicon vias
K. Grigoras, N. Yurttagül, J. -P. Kaikkonen +21
We fabricate and characterize superconducting through-silicon vias and electrodes suitable for superconducting quantum processors. We measure internal quality factors of a million…
Building Blocks of a Flip-Chip Integrated Superconducting Quantum Processor
Sandoko Kosen, Hang-Xi Li, Marcus Rommel +24
We have integrated single and coupled superconducting transmon qubits into flip-chip modules. Each module consists of two chips -- one quantum chip and one control chip -- that are…
Simplified Josephson-junction fabrication process for reproducibly high-performance superconducting qubits
A. Osman, J. Simon, A. Bengtsson +6
We introduce a simplified fabrication technique for Josephson junctions and demonstrate superconducting Xmon qubits with relaxation times averaging above 50s (1.5$\ti…
Phononic loss in superconducting resonators on piezoelectric substrates
Marco Scigliuzzo, Laure E. Bruhat, Andreas Bengtsson +3
We numerically and experimentally investigate the phononic loss for superconducting resonators fabricated on a piezoelectric substrate. With the help of finite element method simul…
Characterizing decoherence rates of a superconducting qubit by direct microwave scattering
Yong Lu, Andreas Bengtsson, Jonathan J. Burnett +8
We experimentally investigate a superconducting qubit coupled to the end of an open transmission line, in a regime where the qubit decay rates to the transmission line and to its o…
Junction-less nanowire based photodetector: Role of nanowire width
Anita Fadavi Roudsari, Iman Khodadadzadeh, Nixon O +2
Enhanced photocurrent is demonstrated in a junction-less photodetector with nanowires embedded in its channel. The fabricated photodetector consists of a large area for efficient a…