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Different from traditional semiconductors, the organic semiconductors normally possess moderate many-body interactions with respect to charge, exciton, spin and phonons. In particular, the diagonal electron-phonon couplings give rise to the spatial localization and the off-diagonal couplings refer to the delocalization. With the competition between them, the electrons are dispersive in a finite extent and unfavorable towards thermal equilibrium. In this context, the quantities from the statistical mechanics such as the entropy have to be reexamined. In order to bridge the localization-delocalization duality and the device performance in organic semiconductors, the quantum heat engine model is employed to describe the charge, exciton and spin dynamics. We adopt the adaptive time-dependent density matrix renormalization group algorithm to calculate the time evolution of the out-of-time-ordered correlator (OTOC), a quantum dynamic measurement of the entanglement entropy, in three models with two kinds of competing many-body interactions: two-bath lattice model with a single electron, Frenkel-charge transfer mixed model, and the Merrifield model for singlet fission. We respectively investigate the parameter regime that the system is in the many-body localization (MBL) phase indicated by the behavior of OTOC. It is recognized that the novel effects of coherent electron hopping, the ultrafast charge separation and the dissociation of triplet pairs are closely related to the MBL effect. Our investigation unifies the intrinsic mechanisms correlating to charge, exciton and spin into a single framework of quantum entanglement entropy, which may help clarify the complicated and diverse phenomena in organic semiconductors.
The magneto-electronic field effects in organic semiconductors at high magnetic fields are described by field-dependent mixing between singlet and triplet states of weakly bound charge carrier pairs due to small differences in their Lande g-factors t
We explore the possibility that hyperfine interaction causes the recently discovered organic magnetoresistance (OMAR) effect. Our study employs both experiment and theoretical modelling. An excitonic pair mechanism model based on hyperfine interactio
We demonstrate that nuclear spin fluctuations lead to the electric current noise in the mesoscopic samples of organic semiconductors showing the pronounced magnetoresistance in weak fields. For the bipolaron and electron-hole mechanisms of organic ma
Separating the influence of hyperfine from spin-orbit interactions in spin-dependent carrier recombination and dissociation processes necessitates magnetic resonance spectroscopy over a wide range of frequencies. We have designed compact and versatil
One of the basic assumptions in organic field-effect transistors, the most fundamental device unit in organic electronics, is that charge transport occurs two-dimensionally in the first few molecular layers near the dielectric interface. Although the