Quantum computers have made extraordinary progress over the past decade, and
significant milestones have been achieved along the path of pursuing universal fault-tolerant …

High-fidelity two-qubit gates at scale are a key requirement to realize the full promise of
quantum computation and simulation. The advent and use of coupler elements to tunably …

High-quality two-qubit gate operations are crucial for scalable quantum information
processing. Often, the gate fidelity is compromised when the system becomes more …

This tutorial aims at giving an introductory treatment of the circuit analysis of
superconducting qubits, ie, two-level systems in superconducting circuits. It also touches …

Maintaining or even improving gate performance with growing numbers of parallel
controlled qubits is a vital requirement for fault-tolerant quantum computing. For …

Tunable coupling of superconducting qubits has been widely studied due to its importance
for isolated gate operations in scalable quantum processor architectures. Here, we …

High fidelity two-qubit gates exhibiting low cross talk are essential building blocks for gate-
based quantum information processing. In superconducting circuits, two-qubit gates are …

We propose a floating tunable coupler that does not rely on direct qubit-qubit coupling
capacitances to achieve the zero-coupling condition. We show that the polarity of the qubit …

We demonstrate a controlled-Z gate between capacitively coupled fluxonium qubits with
transition frequencies 72.3 and 136.3 MHz. The gate is activated by a 61.6-ns-long pulse at …

A major challenge in operating multiqubit quantum processors is to mitigate multiqubit
coherent errors. For superconducting circuits, besides crosstalk originating from imperfect …