Thin Films and Devices of Evaporable Spin Crossover Complexes

Spin states of the spin crossover complexes can be switched reversibly between high spin and low spin under different stimulations such as temperature, pressure, irradiation and magnetic field. Generally, it is also accompanied by the change of color, volume and conductivity, and the thermo-induced magnetic hysteresis. Therefore, they show potential applications in optical/thermal switches, sensors, display, and memory devices. Additionally, high-vacuum evaporation is generally applied to fabricate devices in molecular electronics/spintronics with high-quality and ultra-clean films. However, there are very few evaporable spin crossover complexes which greatly limit their applications. In this paper, we systematically summarize the recent progress of evaporable spin crossover complexes in films and devices. Several reported evaporable spin crossover complexes are discussed, and the effect of the substrate on spin transition has been investigated with different techniques, furthermore, the related conceptual devices are discussed. At the end, the existed difficulties and future trends of spin crossover complexes in device applications are prospected and reviewed to provide useful guidance for the future device developments.