Sun Shih-Jye, Menŝík Miroslav, Toman Petr
Department of Applied Physics, National University of Kaohsiung, Kaohsiung, Taiwan, Republic of China.
Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan, Republic of China.
Phys Chem Chem Phys. 2024 May 1;26(17):13261-13270. doi: 10.1039/d4cp00089g.
A theoretical construction of an antiferromagnetic polymer multilayered field-effect transistor with polymers stretched between the source and drain contacts was undertaken. The model employed a quantum approach to the on-chain spin-charge distribution, which was self-consistently coupled with the charge distribution controlled by the gate voltage. Contrary to standard field-effect transistors, we found that the current firstly increased superlinearly with the drain voltage, then it achieved the maximum for drain voltages notably lower than the gate voltage, and after that, it decreased with the drain voltage with no saturation. Such effects were coupled with the formation of the current spin-polarization ratio, where the on-chain mobility of respective spin-polarized charges was significantly dependent on the applied drain voltage. These effects arise from competition among the antiferromagnetic coupling, the intra-site spin-dependent Coulomb interaction, and the applied drain and gate voltages, which strongly influence the on-chain spin-charge distribution, varying from an alternating spin configuration to a spin-polarized configuration at both ends of the chain. Substantial control over the magnitude of spin-polarized currents was achieved by manipulating gate and drain voltages, showcasing the feasibility of practical applications in spintronics.
我们构建了一个反铁磁聚合物多层场效应晶体管的理论模型，其中聚合物在源极和漏极接触之间拉伸。该模型采用量子方法处理链上的自旋 - 电荷分布，并与由栅极电压控制的电荷分布自洽耦合。与标准场效应晶体管不同，我们发现电流首先随漏极电压超线性增加，然后在漏极电压显著低于栅极电压时达到最大值，之后随漏极电压下降且无饱和现象。这些效应与电流自旋极化率的形成相关联，其中各自旋极化电荷的链上迁移率显著依赖于所施加的漏极电压。这些效应源于反铁磁耦合、位点内自旋相关的库仑相互作用以及所施加的漏极和栅极电压之间的竞争，它们强烈影响链上的自旋 - 电荷分布，使链两端从交替自旋构型变为自旋极化构型。通过操纵栅极和漏极电压，实现了对自旋极化电流大小的实质性控制，展示了其在自旋电子学实际应用中的可行性。
