Suppression of measurement-induced state transitions in cosϕ-coupling transmon readout

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Mori, Cyril, Esposito, Francesca D, Petrescu, Alexandru, Ruela, Lucas, Kumar, Shelender, Suresh, Vishnu Narayanan, Ardati, Wael, Nicolas, Dorian, Cappelli, Giulio, Ranadive, Arpit, Gal, Gwenael Le, Esposito, Martina, Ficheux, Quentin, Roch, Nicolas, Buisson, Olivier
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912573290446848
author Mori, Cyril
Esposito, Francesca D
Petrescu, Alexandru
Ruela, Lucas
Kumar, Shelender
Suresh, Vishnu Narayanan
Ardati, Wael
Nicolas, Dorian
Cappelli, Giulio
Ranadive, Arpit
Gal, Gwenael Le
Esposito, Martina
Ficheux, Quentin
Roch, Nicolas
Buisson, Olivier
author_facet Mori, Cyril
Esposito, Francesca D
Petrescu, Alexandru
Ruela, Lucas
Kumar, Shelender
Suresh, Vishnu Narayanan
Ardati, Wael
Nicolas, Dorian
Cappelli, Giulio
Ranadive, Arpit
Gal, Gwenael Le
Esposito, Martina
Ficheux, Quentin
Roch, Nicolas
Buisson, Olivier
contents Drive-induced unwanted state transitions (DUST) are limiting both for microwave readout and parametric operations of superconducting qubits. Among them, measurement-induced state transitions (MIST) are due to intrinsic resonances described by the readout Hamiltonian. They were previously studied with a qubit linearly coupled to its readout mode, which constitutes the usual readout Hamiltonian. Since MIST can appear even at moderate powers, they limit the readout SNR and the QND readout fidelity. In this work, we study the high-power readout regime in a different transmon readout scheme, implementing a nonlinear coupling called the cosϕ-coupling. This coupling stems from a transmon molecule circuit and has symmetry properties that suppress nonparity-conserving MIST. We succeed in performing multi-state single-shot readout up to the fifth excited state of the transmon, which enables us to identify leakage pathways from the computational subspace. The measurements indicate that the system is free of MIST up to high powers, with more than 300 photons in the readout mode. The MIST can be controllably turned on by breaking the parity symmetry of the coupling using flux-tuning. These experimental results are corroborated by branch analysis and simulations of the classical chaotic dynamics, showing that the cosϕ-coupling is very robust to readout photons compared to the usual transverse coupling.
format Preprint
id arxiv_https___arxiv_org_abs_2509_05126
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Suppression of measurement-induced state transitions in cosϕ-coupling transmon readout
Mori, Cyril
Esposito, Francesca D
Petrescu, Alexandru
Ruela, Lucas
Kumar, Shelender
Suresh, Vishnu Narayanan
Ardati, Wael
Nicolas, Dorian
Cappelli, Giulio
Ranadive, Arpit
Gal, Gwenael Le
Esposito, Martina
Ficheux, Quentin
Roch, Nicolas
Buisson, Olivier
Quantum Physics
Drive-induced unwanted state transitions (DUST) are limiting both for microwave readout and parametric operations of superconducting qubits. Among them, measurement-induced state transitions (MIST) are due to intrinsic resonances described by the readout Hamiltonian. They were previously studied with a qubit linearly coupled to its readout mode, which constitutes the usual readout Hamiltonian. Since MIST can appear even at moderate powers, they limit the readout SNR and the QND readout fidelity. In this work, we study the high-power readout regime in a different transmon readout scheme, implementing a nonlinear coupling called the cosϕ-coupling. This coupling stems from a transmon molecule circuit and has symmetry properties that suppress nonparity-conserving MIST. We succeed in performing multi-state single-shot readout up to the fifth excited state of the transmon, which enables us to identify leakage pathways from the computational subspace. The measurements indicate that the system is free of MIST up to high powers, with more than 300 photons in the readout mode. The MIST can be controllably turned on by breaking the parity symmetry of the coupling using flux-tuning. These experimental results are corroborated by branch analysis and simulations of the classical chaotic dynamics, showing that the cosϕ-coupling is very robust to readout photons compared to the usual transverse coupling.
title Suppression of measurement-induced state transitions in cosϕ-coupling transmon readout
topic Quantum Physics
url https://arxiv.org/abs/2509.05126