Self‐Cooling Molecular Spin Qudits

Palacios, Elías ; Aguilà, David ; Gracia, David ; Maniaki, Diamatoula ; Barrios, Leoní A. ; Chiesa, Alessandro ; Martínez, Jesús I. (Universidad de Zaragoza) ; Novikov, Valentin ; Roubeau, Olivier ; Carretta, Stefano ; Evangelisti, Marco ; Aromí, Guillem ; Luis, Fernando

Resumen: The need of operating molecular spin qubits at very low temperatures constitutes a technological limitation. This challenge is addressed by integrating, in the same material and at the molecular scale, quantum processing and magnetic refrigeration capabilities. The molecular unit is a [GdEr] heterolanthanide coordination complex, where Er(III) encodes a qubit while Gd(III) provides a large magnetocaloric effect. The properties of each component are separately studied in isostructural [LaEr] and [GdLu] complexes, where each functional ion lies next to a diamagnetic metal. All complexes are characterized by magnetic, heat capacity, and EPR measurements. The results show that the presence of both ions in the same molecule has a synergic effect on both functionalities. Thus, the coupling between Er(III) and Gd(III) spins lifts any level degeneracies even close to zero magnetic field, leading to a d = 16 set of spin states that, as revealed by pulse EPR measurements, can be coherently manipulated. In turn, Er(III) enhances the magnetocaloric effect compared to [GdLu], extending it to lower temperatures. This is corroborated by direct magnetocaloric measurements, which show the ability of this material to cool itself, and a device, down to temperatures as low as 0.4 K.

Idioma: Inglés

DOI: 10.1002/adma.202511061

Año: 2025

Publicado en: Advanced materials (2025), e11061 [7 pp.]
ISSN: 0935-9648

Financiación: info:eu-repo/grantAgreement/ES/AEI/AEI PID2022-140923NB-C21
Financiación: info:eu-repo/grantAgreement/ES/DGA/E09-23R-QMAD
Financiación: info:eu-repo/grantAgreement/ES/DGA/E11-23R-M4
Financiación: info:eu-repo/grantAgreement/ES/DGA/E31-23R-PLATON
Financiación: info:eu-repo/grantAgreement/ES/MICINN/CEX2023-001286-S
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PDC2022-133184-I00
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2020-1183294RB-I00
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2021-124734OB-C21
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2022-137764OB-I00
Financiación: info:eu-repo/grantAgreement/EUR/MICINN/TED2021-129214B-I00
Financiación: info:eu-repo/grantAgreement/EUR/MICINN/TED2021-131447B-C21

Tipo y forma: Article (Published version)

Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)