Multipassage Landau-Zener tunneling oscillations in the dual dressing of atomic qubits

Year: 2026

Authors: Fregosi A., Marinelli C., Gabbanini C., Biancalana V., Allegrini M., Arimondo E., Petiziol F., Wimberger S., Fioretti A., Bevilacqua G.

Autors Affiliation: CNR, INO, Via G Moruzzi 1, I-56124 Pisa, Italy; Univ Siena, Dipartimento Sci Fis Terra & Ambiente, Via Roma 56, I-53100 Siena, Italy; Univ Pisa, Dipartimento Fis E Fermi, Largo B Pontecorvo 3, I-56127 Pisa, Italy; CNR, Ist Nanosci, NEST, Piazza S Silvestro 12, I-56127 Pisa, Italy; Tech Univ Berlin, Inst Phys & Astron, Hardenbergstr 36, D-10623 Berlin, Germany; Univ Parma, Dept Math Phys & Comp Sci, Parco Area Sci 7-A, I-43124 Parma, Italy; Natl Inst Nucl Phys INFN, Milano Bicocca Sect, Parma Grp, Parco Area Sci 7-A, I-43124 Parma, Italy.

Abstract: The application of nonresonant electromagnetic fields, a technique known as ’dressing’, provides critical control over the properties of fundamental quantum systems. We investigate the time evolution of a dressed-atom coherent spin ensemble, effectively representing a qubit, driven by a non-resonant electromagnetic field with two components, one along the quantisation static magnetic field and the other one orthogonal to it. While this second component produces a Larmor precession of the spin, the longitudinal dressing modifies the instantaneous field value, leading to a frequency modulated temporal evolution of the spin. This dual-dressing configuration represents an extension of the Landau-Zener multipassage interferometry in the presence of an additional dressing field controlling the tunneling process by its amplitude and phase. Our measurement of the qubit coherence introduces additional features to the transition probability readout of standard interferometry. The coherence time evolution is characterized by oscillations at several frequencies, each of them produced by a different quantum contribution. Such frequency description introduces a new picture of the qubit multipassage evolution. Our tuning-dressed configuration expands the toolbox for quantum state manipulation and quantum control applications. The experiments are performed in rubidium and caesium atomic magnetometers, confined in a magneto-optical trap and in a vapour cell, respectively. Static fields in the documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$mu$$end{document}T range and kHz oscillating fields with large Rabi frequencies are applied. Because the present low-frequency dressing operation does not fall within the standard Floquet engineering paradigm based on the high-frequency expansion, we develop an ad-hoc dressing perturbation treatment. Numerical simulations support the adiabatic and non-adiabatic qubit evolution.

Journal/Review: SCIENTIFIC REPORTS

Volume: 16 (1)      Pages from: 6285-1  to: 6285-12

More Information: E.A. and S. W. acknowledge financial support by: Q-DYNAMO (EU HORIZON-MSCA-2022-SE-01) with project No. 101131418. A. Fr. acknowledges the Italian MUR through the PNRR project EuPRAXIA Advanced Photon Sources (EuAPS) contract EuAPS IR0000030 CUP I93C21000160006 for the support. A. Fi. and S.W. acknowledge financial support from the PNRR MUR project PE0000023-NQSTI financed by the European Union – Next Generation EU. F. P. acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through the Emmy Noether Programme – project number 555842149.
KeyWords: States; Field
DOI: 10.1038/s41598-026-36403-7