Related papers: High Efficiency Carrier Multiplication in PbSe Nan…
We report here an assessment of carrier multiplication (CM) yields in PbSe and PbS nanocrystals (NCs) by a quantitative analysis of biexciton and exciton dynamics in transient photoluminescence decays. Interest in CM, the generation of more…
Carrier multiplication (CM) describes a strong charge-carrier interaction process in semiconductor colloidal nanocrystals (NCs), wherein two band-edge excitons are simultaneously created by an absorbed photon with at least twice the bandgap…
We propose a novel mechanism for photogeneration of multiexcitons by single photons (carrier multiplication) in semiconductor nanocrystals. In this mechanism, the Coulomb interaction between two valence-band electrons involving their…
For Si and Ge nanocrystals (NCs) embedded in wide band-gap matrices, Auger recombination (AR) and carrier multiplication (CM) lifetimes are computed exactly in a three-dimensional real space grid using empirical pseudopotential wave…
We show that bi-exciton formation can be highly efficient in a solar cell with the semiconductor absorber filled with an array of metallic nanoparticles having plasmonic resonance tuned to the semiconductor gap energy. This process can be…
In conventional solar cell semiconductor materials (predominantly Si) photons with energy higher than the band gap initially generate hot electrons and holes, which subsequently cool down to the band edge by phonon emission. Due to the…
We address recent experiments (Science 325, 1367 (2009)) reporting on highly efficient multiplication of electron-hole pairs in carbon nanotube photodiodes at photon energies near the carrier multiplication threshold (twice the…
Carrier multiplication (CM), where the absorption of a single photon results in the generation of several electron-hole pairs via impact ionization, plays a pivotal role in the quest for enhancing the performance of solar cells beyond the…
Being a source of clean and renewable energy, the possibility to convert solar radiation in electric current with high efficiency is one of the most important topics of modern scientific research. Currently the exploitation of interaction…
The intriguing physics of carrier-carrier interactions, which likewise affect the operation of light emitting devices, stimulate the research on semiconductor structures at high densities of excited carriers, a limit reachable at large…
Employing the interband exciton scattering model, we have performed a numerical study of the direct photogeneration and population relaxation processes contributing to carrier multiplication (CM) in nanocrystalline and bulk PbSe. We argue…
Engineering semiconductors to enhance carrier multiplication (CM) could lead to increased photovoltaic cell performance and a significant widening of the materials range suitable for future solar technologies. Semiconductor nanocrystals…
The distribution of rates of carrier multiplication (CM) following photon absorption is calculated for semiconductor nanocrystals (NCs). The NC electronic structure is described using a screened pseudopotential method known to give reliable…
While silicon solar cells dominate global photovoltaic energy production, their continued improvement is hindered by the single junction limit. One potential solution is to use molecular singlet exciton fission to generate two electrons…
Carrier Multiplication (CM) is a Coulomb-driven non-radiative recombination mechanism which leads to the generation of multiple electron-hole pairs after absorption of a single high-energy photon. Recently a new CM process, termed space…
Incorporation of manganese impurities into II-VI semiconductors results in a dramatic change in their properties due to strong exchange interactions between the Mn ion and the semiconductor host. In colloidal quantum dots (QDs), these…
We report on systematic numerical study of carrier multiplication (CM) processes in spherically symmetric nanocrystal (NC) and bulk forms of PbSe and PbS representing the test bed for understanding basic aspects of CM dynamics. The adopted…
Understanding the ultrafast dynamics and transport of photoexcited carriers in topological insulators is crucial for the optical manipulation of spins and may shed light on the nature of topological excitons. Here we investigate…
The power conversion efficiencies (PCEs) of organic solar cells (OSCs) using non-fullerene acceptors (NFAs) have now reached 18%. However, this is still lower than inorganic solar cells, for which PCEs >20% are commonplace. A key reason is…
It was shown in the recent experiments that the hybrid organic/inorganic resonant structures can provide a flexible materials platform aimed at the design of novel light emitting devices. The applications of hybrid structures for…