July 29, 2026 -- The manipulation of individual molecules to harness electron spin—a quantum property that could redefine computing—is rapidly emerging as a frontier in next-generation electronics. A comprehensive new review published in Nano Research explores how single-molecule spin devices are poised to transform this vision into reality, offering a pathway toward ultra-compact, low-power spintronic technologies and molecular-scale quantum information processing.

A collaborative team of scientists led by Xuefeng Guo from Peking University and Chuancheng Jia from Nankai University, together with colleagues from The University of Hong Kong and Beijing Institute of Technology, has systematically outlined the state of single-molecule spintronics to advance the field. The review, titled “Single-Molecule Spin Devices: Fundamentals, Advances, and Prospects,” provides a roadmap for encoding, manipulating and detecting spin at the ultimate limit of miniaturization—the single molecule.

“Single-molecule spintronics represents a paradigm shift in how we think about information processing,” said Xuefeng Guo, corresponding author of the review and a professor at the College of Chemistry and Molecular Engineering, Peking University. “By encoding, manipulating, and detecting electron spin at the level of individual molecules, we can potentially overcome the limitations of conventional electronics and create devices that are not only smaller but also far more energy-efficient.”

At the heart of these devices are molecular systems that possess intrinsic spin—such as single-molecule magnets, spin-crossover complexes, organic radicals, and chiral molecules. Their unique quantum characteristics, including large magnetic anisotropy, switchable spin states, and the chiral-induced spin selectivity effect, make them ideal platforms for investigating fundamental spin phenomena. The integration of these molecules into junctions with advanced measurement techniques—like spin-polarized scanning tunneling microscopy and electron spin resonance—has enabled researchers to observe and control spin transport, coherence, and many-body effects at the atomic scale.

The review highlights a range of spin-related quantum effects that have been demonstrated in single-molecule devices. These include the Kondo effect, where conduction electrons screen a local magnetic moment to produce a characteristic zero-bias conductance peak; spin filtering through magnetic orbitals or quantum interference; spin thermoelectric effects that convert temperature gradients into pure spin currents; and electrically tunable spin coupling. Such effects have been harnessed to create functional device prototypes, including spin valves with magnetoresistance ratios exceeding 1800%, spin switches operable at room temperature, and molecular spin qubits with microsecond coherence times.

“By correlating molecular design with quantum transport mechanisms, we can create a comprehensive roadmap for developing practical devices,” added Chuancheng Jia, professor at the Center of Single-Molecule Sciences, Nankai University. “This molecular-level control over spin states opens up possibilities for quantum information processing platforms that operate at scales previously confined to science fiction.”

One of the critical challenges in the field is device reproducibility and stability. Variations in binding geometry, local electrostatic environment, and molecule-electrode coupling can lead to significant fluctuations in spin readout and control. To address this, the team advocates for large-scale statistical measurements, standardized reference molecules, and the use of two-dimensional electrodes with van der Waals gaps to improve interface quality. For quantum applications, isotopic purification and engineering of clock transitions may extend coherence times, while integration with microwave resonators could enable coherent coupling to photons.

The researchers expect the review to accelerate the development of molecular spin‑based technologies that could eventually complement or surpass conventional silicon electronics. “In the same molecular junction, we can envision integrating memory, logic, and sensing functions by exploiting different spin degrees of freedom,” said Mingliang Li, corresponding author from the University of Hong Kong and Beijing Institute of Technology. “With continued advances in molecular design, interfacial engineering, and quantum-coherent control, single-molecule spin devices are poised to evolve from precision testbeds into functional building blocks for low-power spin logic and chemically defined quantum technologies.”