相关论文: Optoelectronic excitations and photovoltaic effect…
It is known that silicon is an indirect band gap material, reducing its efficiency in photovoltaic applications. Using surface plasmons in metallic nanoparticles embedded in a solar cell has recently been proposed as a way to increase the…
Electron-hole pairs in semiconductors are essential for solar cells and fast electronic circuitry, but the competition between carrier transport and relaxation into heat limits the efficiency and speed. Here we use ultrafast electron…
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…
It is well known that phonons can overscreen the bare Coulomb electron-electron repulsion, turning it into the effective attraction that binds the Cooper pairs responsible for BCS superconductivity. Here, we use a simple lattice model to…
Reversible exchange of photons between a material and an optical cavity can lead to the formation of hybrid light--matter states where material properties such as the work function\cite{Hutchison_AM2013a}, chemical…
Polaritons, formed as a result of strong hybridization of matter with light, are promising for important applications including organic solar cells, optical logic gates, and qubits. Owing to large binding energies of Frenkel excitons…
We investigate the interaction of strongly correlated electrons with phonons in the frame of the Hubbard-Holstein model. The electron-phonon interaction is considered to be strong and is an important parameter of the model besides the…
Research into the efficiency of photosynthetic light harvesting has focused on two factors: (1) entanglement of chromophores, and (2) environmental noise. While chromophores are conjugated $\pi$-bonding molecules with strongly correlated…
In this article, we investigate the effect of prolonged light exposure on silicon heterojunction solar cells. We show that, although light exposure systematicallyimproves solar cell efficiency in the case of devices using intrinsic and…
Excitonic semiconductors such as transition metal dichalcogenides (TMDCs) are attractive for next-generation photovoltaics (PVs) with low cost, light weight, and low material consumption. In WS2 and other TMDCs, the simultaneous large…
The electron-hole pair created via photon absorption in organic photoconversion systems must overcome the Coulomb attraction to achieve long-range charge separation. We show that this process is facilitated through the formation of excited,…
Coupled two-dimensional electron-hole bilayers provide a unique platform to study strongly correlated Bose-Fermi mixtures in condensed matter. Electrons and holes in spatially separated layers can bind to form interlayer excitons, composite…
We present a further investigation into the increased ionization observed in element charge states in the fast solar wind compared to its coronal hole source regions. Once ions begin to be perpendicularly heated by ion cyclotron waves and…
The generation of a current by light is a key process in optoelectronic and photovoltaic devices. In band semiconductors, depletion fields associated with interfaces separate long-lived photo-induced carriers. However, in systems with…
Carrier thermalization in a superlattice solar cell made of polar semiconductors is studied theoretically by considering a minimal model where electron-phonon scattering is the principal channel of carrier energy loss. Importantly, the…
Photons do not carry sufficient momentum to induce indirect optical transitions in semiconducting materials such as silicon, necessitating the assistance of lattice phonons to conserve momentum. Compared to direct bandgap semiconductors,…
We discuss the photovoltaic effect at a p-n heterojunction, in which the illuminated side is a doped Mott insulator, using the simplest description of a Mott insulator within the Hubbard model. We find that the internal quantum efficiency…
In a superconductor electrons form pairs despite the Coulomb repulsion as a result of an effective attractive interaction mediated by, for example phonons. In the present paper DeGennes' description of the dynamically screened Coulomb…
Ionization of matter by energetic radiation generally causes complex secondary reactions which are hard to decipher. Using large helium nanodroplets irradiated by XUV photons, we show that the full chain of processes ensuing primary…
Photo-induced insulator-metal transition in VO$_2$ and the related transient and multi-timescale structural dynamics upon photoexcitation are explained within a unified framework. Holes created by photoexcitation weaken the V-V bonds and…