11 papers
Heralded Leakage Detection with Preserved Computational-State Coherence in a Fixed-Frequency Transmon
Takeaki Miyamura, Zhiling Wang, Peter A. Spring +5
Leakage out of the computational subspace is a major error mechanism in superconducting quantum processors. Detecting leakage without disturbing the encoded quantum information can…
QuBE/Qubex: an integrated hardware-software system for superconducting qubit experiments with broadband control
Akinori Machino, Kazuhisa Ogawa, Takefumi Miyoshi +21
Achieving high-fidelity operation in large-scale superconducting qubit systems requires not only control hardware with broad frequency coverage, low crosstalk, and tight synchroniz…
Systematic frequency-collision analysis of the cross-resonance gate outside the straddling regime
Shinichi Inoue, Shotaro Shirai, Shuhei Tamate +4
Frequency crowding remains a major obstacle to scaling fixed-frequency transmon processors. Among the widely used all-microwave two-qubit gates, the cross-resonance (CR) gate is pa…
Quantum Magic in early FTQC: From Diagonal Clifford Hierarchy No-Go Theorems to Architecture Design Blueprints
Hsueh-Hao Lu, Yasunari Suzuki, Yasunobu Nakamura +1
We address the circuit-design problem of maximizing quantum magic in early fault-tolerant quantum computing (early FTQC), where logical dynamics natively take the form of alternati…
Wave--particle transition and quantum Zeno effect in which-way experiments with a superconducting quantum processor
Shiyu Wang, Zhiguang Yan, Clemens Gneiting +3
Wave--particle duality demonstrates the peculiar nature of quantum mechanics. In which-way experiments, depending on the measurement scheme, a particle exhibits either wave-like or…
High-gain and large-bandwidth Josephson parametric amplifier influenced by Fabry-Pérot interference
Shingo Kono, Jesper Ilves, Arjan F. van Loo +8
Quantum-limited parametric amplifiers are essential components for many quantum technologies operating in the microwave domain. Achieving both high gain and broad bandwidth, howeve…