Enabling ambient stability and quantum integration of organometallic magnonic ferrimagnets via atomic layer encapsulation
Magnons, the quanta of spin waves in magnetic materials, are promising for hybrid quantum systems by bridging electromagnetic and spin degrees of freedom. The organometallic ferrimagnet vanadium tetracyanoethylene (V[TCNE]<sub>x</sub>, x ≈ 2) is especially well-suited for quantum magnonics due to its low Gilbert damping and substrate versatility. However, its rapid chemical degradation in ambient conditions hinders practical applications. Incumbent encapsulation methods provide some protection, but are bulky, obscure intrinsic properties of V[TCNE]<sub>x</sub>, introduce thermal stress at cryogenic temperatures, and complicate microwave device integration. Here, we demonstrate that ultrathin alumina films deposited via low-temperature atomic layer deposition effectively protect V[TCNE]<sub>x</sub> by preserving its magnetic and magnonic properties following ambient exposure. The sub-100 nm transparent films also enable advanced spectroscopy, magnetometry, and cavity magnonic measurements that reveal the intrinsic properties of V[TCNE]<sub>x</sub>. This encapsulation strategy advances molecule-based quantum information science by providing a robust route toward scalable, monolithic integration in hybrid quantum technologies.
Authors
- Dmitry Lebedev (ORCID: https://orcid.org/0000-0002-1866-9234)
- Mark C. Hersam (ORCID: https://orcid.org/0000-0003-4120-1426)
- Srishti Pal (ORCID: https://orcid.org/0000-0002-8253-2144)
- Seok Daniel Namgung (ORCID: https://orcid.org/0000-0001-6049-0433)
- Ezekiel Johnston‐Halperin (ORCID: https://orcid.org/0000-0002-6240-3505)
- Hong Youl Park (ORCID: https://orcid.org/0000-0002-7618-7655)
- Donley S. Cormode
- George Chappell Schatz (ORCID: https://orcid.org/0000-0001-5837-4740)
- Subhajyoti Chaudhuri (ORCID: https://orcid.org/0000-0001-8297-1123)
- M. Iqbal Bakti Utama (ORCID: https://orcid.org/0000-0002-4454-8348)
- Qin Xu (ORCID: https://orcid.org/0000-0001-9311-213X)
- Gregory D. Fuchs (ORCID: https://orcid.org/0000-0003-4343-8523)
- Robert Claassen
Institutions
- Northwestern University (US)
- University of Geneva (CH)
- Cornell University (US)
- The Ohio State University (US)
- Chung-Ang University (KR)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-11-26
- DOI
- https://doi.org/10.1038/s41467-025-65588-0
- Primary Topic
- Magnetism in coordination complexes
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- U.S. Department of Energy
- Northwestern University
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Office of Science
- Cornell Center for Materials Research
- Materials Research Science and Engineering Center, Harvard University
- Materials Research Science and Engineering Center, Northwestern University
- Division of Materials Research
- Division of Electrical, Communications and Cyber Systems
- Basic Energy Sciences