Achieving Significant Multilevel Modulation in Superior-quality Organic Spin Valve.

Organic semiconductors, characterized by their exceptionally long spin relaxation times (≈ms) and unique spinterface effects, are considered game-changers in spintronics. However, achieving high-performance and wide-range tunable magnetoresistance (MR) in organic spintronic devices remains challenging, severely limiting the development of organic spintronics. This work combines straintronic multiferroic heterostructures with organic spin valve (OSV) to develop a three-terminal OSV device with a gate structure. The device exhibits a record-high MR ratio of 281% which 10 times higher than the average in polymer systems. More importantly, this work can perform multilevel writing operations on the device using gate voltages and create at least 10 stable spin-dependent working states within a single device. Both experiments and theoretical calculations confirm such an extraordinary tunability range originates from the synergistic effects of strain and charge accumulation that amplified by the spinterface. This study demonstrates the potential of OSV systems for efficient spin manipulation and highlights the spinterface as an ideal platform for amplifying spin effects for next-generation spintronic devices.