Modeling of positive and negative organic magnetoresistance in organic light-emitting diodes

Zhang, Sijie; Rolfe, N. J.; Desai, Pratik; Shakya, P.; Drew, Alan J.; Kreouzis, Theo; Gillin, W. P.

doi:10.1103/physrevb.86.075206

Cited by 24 publications

(11 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Up to now, a great number of unipolar [1,16] and bipolar [3,[17][18][19][20] devices have been fabricated and studied. Several theories have been proposed to explain the effects, involving excitons [3], polaron pairs [21,22] or bipolarons [7].…”

Section: Introductionmentioning

confidence: 99%

Trap effect of triplet excitons on magnetoresistance in organic devices

Yang

Zhang

Meng

et al. 2015

Organic Electronics

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Trap effect of triplet excitons on magnetoresistance in organic devices

Yang

Zhang

Meng

et al. 2015

Organic Electronics

View full text Add to dashboard Cite

“…B 1 , B 2 and B 3 are the saturation fields, similar to Ref. [16,19,25,26], with ~2.1 mT, ~4.9 mT and ~127 mT respectively. The two Lorentzian terms describing the magnetic field tuned ISC (blue line) and RISC (green line) respectively, resulting in positive and negative LFC; and the non-Lorentzian term is for HFC denoting the magnetic field dependent TCA process (magenta line).…”

Section: Le and 3 Ct In "Scatteringmentioning

confidence: 89%

“…The equation is as follows: where the first two terms are Lorentzian functions describing the magnetic field mediated ISC and RISC respectively, resulting in positive and negative LFC; 12,16,22,25 and the third term is non-Lorentzian function for HFC denoting the magnetic field dependent TCA process, 26 and its sign could clearly represent the outcome of TCA (i.e., "Scattering Channel" or "Dissociation Channel"). During the fitting, B is the applied magnetic field.…”

Section: Le and 3 Ct In "Scatteringmentioning

confidence: 99%

The triplet-charge annihilation in copolymer-based organic light emitting diodes: through the “Scattering Channel” or the “Dissociation Channel”?

Yuan

Niu

Chen

et al. 2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

In organic semiconductors, the triplet-charge annihilation (TCA) is one of the most common excitonic interactions influencing the opto-electronic power conversion efficiency of the devices. However, it is still unclear whether the TCA reaction goes through the "Scattering Channel" or the "Dissociation Channel". In this work, by measuring the organic magneto-current (OMC) of the conjugated co-polymer poly[{9,9-dioctyl-2,7-divinylene-fluorenylene}-alt-co-{2-methoxy-5-(2-ethylhexyloxy)-1,4-phenyene}] (PFOPV)-based organic light-emitting diodes (OLEDs) containing both localized exciton (LE) and charge-transfer-complex (CT), it is found that (3)LE and (3)CT play a crucial role in the "Scattering Channel" and the "Dissociation Channel" of TCA, respectively. This argument was supported by the simulations of Lorentzian and non-Lorentzian functions used, respectively, for intersystem crossing (or reverse intersystem crossing, RISC) and TCA effects. Moreover, by inserting a tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane (3TPYMB) layer between PFOPV and the cathode, we improved the electroluminescence efficiency of PFOPV-based OLEDs by suppressing the TCA when (3)CT involves in RISC. Our results give insights into the spin-dependent TCA limiting the efficiency of hotly discussed CT-based OLEDs.

show abstract

“…In addition, our results basically agree with previous works that the negative component in MC responses is correlated with the interaction between triplet excitons with charges. 9,14,25 In this study, the design of the hole-blocking device further enhances the triplet exciton-charge reaction, thereby modulating the line shape of MC responses.…”

Section: -6mentioning

confidence: 99%

Modulating the line shape of magnetoconductance by varying the charge injection in polymer light-emitting diodes

et al. 2018

View full text Add to dashboard Cite

We fabricate the phenyl-substituted poly(p-phenylene vinylene) copolymer (super yellow, SY-PPV)-based polymer light-emitting diodes (PLEDs) with different device architectures to modulate the injection of opposite charge carriers and investigate the corresponding magnetoconductance (MC) responses. At the first glance, we find that all PLEDs exhibit the positive MC responses. By applying the mathematical analysis to fit the curves with two empirical equations of a non-Lorentzian and a Lorentzian function, we are able to extract the hidden negative MC component from the positive MC curve. We attribute the growth of the negative MC component to the reduced interaction of the triplet excitons with charges to generate the free charge carriers as modulated by the applied magnetic field, known as the triplet exciton-charge reaction, by analyzing MC responses for PLEDs of the charge-unbalanced and hole-blocking device configurations. The negative MC component causes the broadening of the line shape in MC curves.

show abstract

Modeling of positive and negative organic magnetoresistance in organic light-emitting diodes

Cited by 24 publications

References 58 publications

Trap effect of triplet excitons on magnetoresistance in organic devices

Trap effect of triplet excitons on magnetoresistance in organic devices

The triplet-charge annihilation in copolymer-based organic light emitting diodes: through the “Scattering Channel” or the “Dissociation Channel”?

Modulating the line shape of magnetoconductance by varying the charge injection in polymer light-emitting diodes

Contact Info

Product

Resources

About