Investigating Underlying Mechanisms for Nonfullerene Hybrid Bulk Heterojunctions‐Based Organic Magnetoresistance

Abstract

such as electric fields, magnetic fields, and polarized light. [1] When an output electrical signal such as resistance varies with respect to a changing magnetic field in the dark environment for an organic semiconductor, the so-called organic magnetoresistance (OMR) is developed. In fact, many organic semiconductors that include polymers and small molecular materials have been recognized as desirable candidates for spintronic applications, on account of their long spin relaxation times and easy spin manipulation. [2,3] Basically, the OMR effect does not require ferromagnets and is the innate property of organic semiconductors. This makes it distinct from organic spin valves (SVs) and magnetic tunnel junctions (MTJs). [4][5][6] In those

Enhanced Self-Stimulated Dissociation in Non-fullerene Layer-by-Layer Organic Solar Cells through Superimposed and Oriented Dipolar Polarization

“…It should be noted the thermal spin polarization and microscopic mechanisms such as phase separation and material crystallinities can contribute to the characteristic line shape. 57 Furthermore, it is interesting to compare the non-fullerene LBL with the non-fullerene BHJ by separately exciting the donor and acceptor components. In the non-fullerene BHJ, we can see in Figure 3b that the magneto-photocurrent signal amplitude is decreased from −1.75 to −0.98% at 900 mT when the 721 nm excitation is increased from 2.3 to 9.4 mW/cm 2 at a constant intensity (52.6 mW/cm 2 ) of 532 nm beam.…”

Anisotropic Organic Magnetoresistance in Fused-Ring Electron-Acceptor-Based Bulk Heterojunction Systems

“…Previously, we have demonstrated some remarkable magneto-photocurrent and the OMR effect in typical PM6:Y6 and PBDB-T:ITIC based organic BHJs. , Our measurements have shown robust magnetic switching for the systems with clearly high and low resistive states under ambient conditions. Furthermore, we have adopted microscopically theoretical models for analyzing high-field organic magnetoresistance (HFOMR) and low-field magnetoresistance (LFOMR) systematically . Nevertheless, anisotropic organic magnetoresistance (AOMR) remains unknown at the moment.…”

“…We postulate that the generations of AOMR are primarily attributed to the anisotropic Δ g and HF induced spin mixing mechanism. In addition to this, the negative sign of the AOMR effect indicate that the triplet exciton-polaron interaction and spin coulomb blockade mechanism are mutually responsible for the electrical transport (Figure S2 in the Supporting Information) . By changing the molecular acceptor Y6 to IT-4F, we experimentally find that the 2-fold symmetry of AOMR can be detected for the PM6:IT-4F system as well (see Figures a–d).…”

“…Furthermore, we have adopted microscopically theoretical models for analyzing high-field organic magnetoresistance (HFOMR) and low-field magnetoresistance (LFOMR) systematically. 22 Nevertheless, anisotropic organic magnetoresistance (AOMR) remains unknown at the moment. In principle, it is widely recognized that organic molecular films possess the energetic disorder character due to random distributions and weak intermolecular van der Waals forces.…”

“…More details about the organic spintronic device fabrication can be found in our early work. 22 In short, prior to the device fabrication, transparent indium tin oxide-coated glass (ITO(glass)) substrates were cleaned by standard chemical means using isopropanol, acetone, and ethanol in an ultrasonic bath. They were dried by blowing with a pure nitrogen gas and subsequently experienced a plasma oxidation.…”