Impact of nanostructure configuration on the photovoltaic performance of quantum dot arrays

Abstract

In this work, a mesoscopic model based on the non-equilibrium Green's function formalism for a tight-binding-like effective Hamiltonian is used to investigate a selectively contacted quantum dot array designed for operation as a single junction quantum dot solar cell. By establishing a direct relation between nanostructure configuration and optoelectronic properties, the investigation reveals the influence of inter-dot and dot-contact coupling strengths on the rates of charge carrier photogeneration, radiative recombination, and extraction at contacts, and consequently on the ultimate performance of photovoltaic devices with finite quantum dot arrays as the active medium. For long carrier lifetimes, the dominant configuration effects originate in the dependence of the joint density of states on the inter-dot coupling in terms of band width and effective band gap. In the low carrier lifetime regime, where recombination competes with carrier extraction, the extraction efficiency shows a critical dependence on the dot-contact coupling.

11 pages, 15 figures; extensively revised and substantially extended version

References in corpus (6)

• Theory and simulation of quantum photovoltaic devices based on the non-equilibrium Green's function formalism
• Quantum-kinetic theory of photocurrent generation via direct and phonon-mediated optical transitions
• Quantum-kinetic theory of steady-state photocurrent generation in thin films: Coherent versus incoherent coupling
• Quantum transport in semiconductor quantum dot superlattices: electron-phonon resonances and polaron effects
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Cited by in corpus (5)

• A Microscopic Perspective on Photovoltaic Reciprocity in Ultrathin Solar Cells
• Photocarrier extraction in GaAsSb/GaAsN type-II QW superlattice solar cells
• Nonequilibrium theory of the conversion-efficiency limit of solar cells including thermalization and extraction of carriers
• Entropy production in photovoltaic-thermoelectric nanodevices from the non-equilibrium Green's function formalism
• Quantum-kinetic perspective on photovoltaic device operation in nanostructure-based solar cells