1：Experimental Design and Method Selection:

The study used single crystal tetracene field-effect transistors (FETs) to investigate spin-dependent processes, specifically singlet fission, under magnetic fields. Devices were fabricated with two types of gate dielectrics (Cytop and SiO2) to compare effects. Electrical and magnetic field measurements were conducted at room temperature.

2：Sample Selection and Data Sources:

Tetracene single crystals were grown by physical vapor transport under argon flow. Crystals were laminated onto prefabricated device substrates with photolithographically defined metal electrodes (palladium/titanium or platinum/titanium). Channel lengths ranged from 5 μm to 100 μm.

3：List of Experimental Equipment and Materials:

Equipment included a probe station with an attached electromagnet, fiber optic illuminator, silicon photodiode for intensity measurement, and devices fabricated with Cytop or SiO2 gate dielectrics. Materials included tetracene crystals, palladium, titanium, platinum, Cytop (amorphous fluoropolymer), silicon dioxide, and octadecyltrichlorosilane for surface treatment.

4：Experimental Procedures and Operational Workflow:

FETs were measured under nitrogen gas to minimize degradation. Illumination was provided via a fiber optic illuminator through a glass window. Magnetic fields were swept between -230 mT and 230 mT. Drain current (ID) was measured with constant gate-source (VGS) and drain-source (VDS) voltages. Magnetoconductance (MC) was calculated as [ID(B) – ID(B=0)] / ID(B=0). Angular dependence measurements involved rotating the FET relative to the magnetic field axis.

5：0). Angular dependence measurements involved rotating the FET relative to the magnetic field axis. Data Analysis Methods:

5. Data Analysis Methods: Data were analyzed to observe MC changes. Numerical simulations based on a model by Timmel et al. were used to interpret results, involving calculations of triplet pair state energies and MC using spin Hamiltonian equations.