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arXiv · 2606.03815

A Tutorial for Characterizing Transmon Qubits

Alexandre M. Souza·Davi A. D. Chaves·Carmem M. Gilardoni·Roberto S. Sarthour·João P. Sinnecker·Ivan S. Oliveira
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Abstract

Superconducting transmon qubits are a leading technology for quantum information processing, yet their reliable operation rests on meticulous calibration and characterization routines. These processes have been fine-tuned and are relatively well understood by the quantum computing community. Nevertheless, it is often challenging for newcomers to compile all the available information into a practical experimental flow. In this tutorial, we present a comprehensive walkthrough for the characterization and optimization of tunable transmon qubits, demonstrated on a commercial five-qubit processor. Moving beyond theoretical description, we detail in a straightforward manner the complete workflow, from cryogenic setup and wiring to parametric amplifier optimum operation, flux sweet-spot identification, pulse calibration, and readout optimization. We also demonstrate the characterization of qubit-qubit coupling, covering all steps before multiqubit operations. This guide serves as a reference for experimentalists seeking to efficiently bring up transmon-based quantum devices.

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Alexandre M. Souza, Davi A. D. Chaves, Carmem M. Gilardoni, Roberto S. Sarthour, João P. Sinnecker, Ivan S. Oliveira. 2026-06-02. A Tutorial for Characterizing Transmon Qubits. https://arxiv.org/abs/2606.03815

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