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El texto completo de este trabajo no se encuentra disponible por no haber sido facilitado aún por su autor, por restricciones de copyright, o por no existir una versión digital. Artículo firmado por 26 autores, The Josephson effect results from the coupling of two superconductors across a spacer such as an insulator, a normal metal or a ferromagnet to yield a phase coherent quantum state. However, in junctions with ferromagnetic spacers, very long-range Josephson effects have remained elusive. Here we demonstrate extremely long-range (micrometric) high-temperature (tens of kelvins) Josephson coupling across the half-metallic manganite La0.7Sr0.3MnO3 combined with the superconducting cuprate YBa2Cu3O7. These planar junctions, in addition to large critical currents, display the hallmarks of Josephson physics, such as critical current oscillations driven by magnetic flux quantization and quantum phase locking effects under microwave excitation (Shapiro steps). The latter display an anomalous doubling of the Josephson frequency predicted by several theories. In addition to its fundamental interest, the marriage between high-temperature, dissipationless quantum coherent transport and full spin polarization brings opportunities for the practical realization of superconducting spintronics, and opens new perspectives for quantum computing. Josephson coupling over micrometres and at tens of kelvins is demonstrated across the half-metallic manganite La0.7Sr0.3MnO3 combined with the superconducting cuprate YBa2Cu3O7., Unión Europea, Gobierno de España, IDEX Paris-Saclay, Agence Nationale de la Recherche (ANR), Flag ERA ERA-NET To2Dox project, Ministry of Science and Higher Education of the Russian Federation, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub