A 3D-assembled endohedral nitrogen fullerene in a metal-organic framework toward spin qubit and quantum sensors

To realize quantum information processing, quantum bits are required to have considerable quantum coherence, addressability, and scalability. Arranging and stacking the high-dimensional quantum bits with superior coherence is an important approach to realizing the scalability of quantum systems. Endohedral nitrogen fullerene is a promising molecule-based quantum material with a long quantum coherence time, which is expected to be applied to the construction of high-dimensional quantum bit arrays for quantum information processing. In this work, endohedral nitrogen fullerene molecules were embedded in a 3D metal-organic framework yielding N@C 60 @MOF-177. X-band electron paramagnetic characterization of the energy levels and spin dynamics shows that this system can be used as a spin qubit. The magnitude of the zero-field splitting of the system at low temperatures was properly resolved. Furthermore, the influencing factors on the spin coherence time at low temperatures were investigated by spin dynamic characterization, and the presence of the proton in the environment was detected by ESEEM experiments, which further reveals the feasibility of N@C 60 as a spin quantum sensor. A molecule-based spin qubit and quantum sensor candidate, N@C 60 , was developed to detect the 1 H nuclei in a metal-organic framework through pulsed-EPR.