Transient currents in a molecular photo-diode

Abstract

Light-induced charge transmission through a molecular junction (molecular diode) is studied in the framework of a HOMO-LUMO model and in using a kinetic description. Expressions are presented for the sequential (hopping) and direct (tunneling) transient current components together with kinetic equations governing the time-dependent populations of the neutral and charged molecular states which participate in the current formation. Resonant and off-resonant charge transmission processes are analyzed in detail. It is demonstrated that the transient currents are associated with a molecular charging process which is initiated by photo excitation of the molecule. If the coupling of the molecule to the electrodes is strongly asymmetric the transient currents can significantly exceed the steady state current.Comment: 17 pages, 12 figures, accepted for publication in Chemical Physic

Conductance Mechanism in a Linear Non-Conjugated Trimethylsilyl-Acetylene Molecule: Tunneling Through Localized States

“…Therefore, it is more convenient to employ a description based on the kinetic theory of charge transmission. Last years this theory has been adapted especially for the studies of transient and steady state currents in molecular junctions [39][40][41][42][43][44].…”

“…In line with the kinetic theory, a tunnel current I through the LMR-system can be calculated with use of expression [39,41,42,44] …”

Impact of Gate Potential on the Electroluminescence of the Molecular Photodiode

“…Ìеханізм непружньої трансмісії зумовлений стрибковими та дистанційними суперобмінними електрон-транспортними процесами, в яких беруть участь зарядово-нейтральні та йонізовані стани молекули [14][15][16][17]. При цьому фотоемісія може бути уніабо біполярною [11,18], що залежить від розподілу електронної густини на молекулярних орбіталях (ÌО), які беруть участь в електронній трансмісії.…”

“…HL E      (див. подробиці в [16][17][18]), і, таким чином, за допомогою (10) одержуємо аналітичну залежність трансмісійних щілин (9)…”

Transient probing of the symmetry and the asymmetry of electron interference

“…[11][12][13] The transient currents induced by optical excitations on molecular transport devices are interesting for their relevance to optical switches. [14][15][16][17][18] Real-time migrations of electrons between molecules and conduction † Deceased, June 22nd, 2013 channels are on the focus in some energy 19 and material applications. 20 Particularly for nanoelectronic systems, steering the transient currents can potentially offer versatile resources for timely operating quantum electronic circuits at nanoscale.…”