96 citations · 317 across the 15 of their papers we have counts for
17 papers
Optimal robust single-qubit gates in superconducting quantum processors
Tangyou Huang, Anuj Aggarwal, Jingjun Zhu +11
Fault-tolerant quantum computing requires high-fidelity quantum gates that are resilient to control errors and device imperfections. Here, we develop energy-optimal control pulses…
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…
Electrical post-fabrication tuning of aluminum Josephson junctions at room temperature
Christian Križan, Maurizio Toselli, Irshad Ahmad +11
Josephson junctions are key elements of superconducting quantum technology, serving as the core building blocks of superconducting qubits. We present an experimental study on room-…
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…
Neural-network-based design and implementation of fast and robust quantum gates
Marko Kuzmanović, Ilya Moskalenko, Yu-Han Chang +11
We present a continuous-time, neural-network-based approach to optimal control in quantum systems, with a focus on pulse engineering for quantum gates. Leveraging the framework of…
Quantum Process Tomography with Digital Twins of Error Matrices
Tangyou Huang, Akshay Gaikwad, Ilya Moskalenko +19
Accurate and robust quantum process tomography (QPT) is crucial for verifying quantum gates and diagnosing implementation faults in experiments aimed at building universal quantum…
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…
Quantum SWAP gate realized with CZ and iSWAP gates in a superconducting architecture
Christian Križan, Janka Biznárová, Liangyu Chen +19
It is advantageous for any quantum processor to support different classes of two-qubit quantum logic gates when compiling quantum circuits, a property that is typically not seen wi…
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…
Characterization of process-related interfacial dielectric loss in aluminum-on-silicon by resonator microwave measurements, materials analysis, and imaging
Lert Chayanun, Janka Biznárová, Lunjie Zeng +9
We systematically investigate the influence of the fabrication process on dielectric loss in aluminum-on-silicon superconducting coplanar waveguide resonators with internal quality…
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…
Mitigation of interfacial dielectric loss in aluminum-on-silicon superconducting qubits
Janka Biznárová, Amr Osman, Emil Rehnman +9
We demonstrate aluminum-on-silicon planar transmon qubits with time-averaged energy relaxation times of up to , corresponding to Q = 5 million, and a highest obs…
Experimentally verified, fast analytic and numerical design of superconducting resonators in flip-chip architectures
Hang-Xi Li, Daryoush Shiri, Sandoko Kosen +10
In superconducting quantum processors, the predictability of device parameters is of increasing importance as many labs scale up their systems to larger sizes in a 3D-integrated ar…
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…
Transmon qubit readout fidelity at the threshold for quantum error correction without a quantum-limited amplifier
Liangyu Chen, Hang-Xi Li, Yong Lu +17
High-fidelity and rapid readout of a qubit state is key to quantum computing and communication, and it is a prerequisite for quantum error correction. We present a readout scheme f…
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…