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Updated: Sep 14, 2025

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Near-Room-Temperature Phase Gate in a Molecular High-Spin Qudit of Cocrystallized Endofullerene
Qi Xiong1, Yi-Han Wang2, Peng-Xiang Fu2
1Spin-X Institute, School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, South China University of Technology, Guangzhou 511442, China.
Abstract:
Paramagnetic molecules with high-spin centers can accommodate multilevel spin manipulations. In the cocrystal PdF20TPP·C60/N@C60·8Benzene (ENF-PdTPP), 14N@C60 (S = 3/2) exhibits distinct transition addressability in the frequency domain and a long quantum coherence time (T2 ≈ 5.47 μs at 250 K), making it a promising candidate for multilevel qudit applications. A three-level superposition state was prepared at near-room temperature (250 K) and validated by quantum phase interference. By varying the evolution time (Δτ) of the three-level superposition state, a controllable quantum phase effect has been observed. We found that such a phenomenon can be harnessed as a resource for coherent manipulation for the realization of a fast controlled-phase (C-phase) gate (23.5 MHz), enriching the potential of this high-spin system for quantum algorithm implementations.
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