相关论文: First-principles analysis of the intermediate band…
Introducing an isolated intermediate band (IB) into a wide band gap semiconductor can potentially improve the optical absorption of the material beyond the Shockley-Queisser limitation for solar cells. Here, we present a systematic study of…
The intermediate band (IB) cell is a concept of highly efficient solar cells proposed by Luque and Marti in 1997. The IB concept uses nonlinear effect of two photon absorption enforced with concentration of such photons for generation of…
New generation Indium based lead-free Cs2InAgCl6 is a promising halide material in photovoltaic applications due to its good air stability and non-toxic behavior. But its wide band gap (>3 eV) is not suitable for solar spectrum and hence…
Recombination through quantum dots (QDs) is a major factor that limits efficiency of QD intermediate-band (IB) solar cells. Our proposal for a new IB solar cell based on type-II GaSb QDs located outside the depletion region of a GaAs…
We propose a new intermediate band GaAs solar cell comprising an AlxGa1-xAs absorber with built-in GaSb type-II quantum dots (QDs) [a gradual AlxGa1-xAs absorber with built-in AlyGa1-ySb QDs (0<x=y<0.40) as a variant] separated from the…
By means of the first-principles density functional theory (DFT), I2-II-IV-VI4 type Cu-based quaternary chalcogenides Cu 2 XSiS 4 (X = Ge, Sn, and Pb) have been thoroughly investigated. We report the study of Ge and Sn substitution in the…
We investigated the current-voltage characteristic of InAs/GaAs quantum dot intermediate band solar cells (QD IBSCs) with different n-type doping density in the QD layer. The n-type doping evidently increases the open circuit voltage,…
Intermediate band solar cells (IBSCs) pursue the increase in efficiency by absorbing below-bandgap energy photons while preserving the output voltage. Experimental IBSCs based on quantum dots have already demonstrated that both…
As an appealing concept for developing next-generation solar cells, intermediate-band solar cells (IBSCs) promise to drastically increase the quantum efficiency of photovoltaic conversion. Yet to date, a standing challenge lies in the lack…
Semiconductor heterostructures capable of separating photogenerated electrons and holes have a wide range of optoelectronic applications, including photodetectors, solar cells, and photocatalysts. ${\beta}$-Ga$_2$O$_3$ and rutile GeO$_2$…
We investigate the electronic structure and defect properties of Sn- and Ge- doped ZnTe by first-principles calculations within the DFT+$GW$ formalism. We find that $(\text{Sn}_\text{Zn})$ and $(\text{Ge}_\text{Zn})$ introduce isolated…
We used AlGaSb/AlGaAs material system for a theoretical study of photovoltaic performance of the proposed GaAs-based solar cell in which the type-II quantum dot (QDs) absorber is spatially separated from the depletion region. Due to…
Sulphurization processes in Cu(In,Ga)Se$_2$ thin-film solar cells has been intensively studied in the last decade as a viable alternative to the existing Ga-grading. The main advantage of using S grading is that by substituting Se with S we…
Alloying small quantities of silver into Cu(In,Ga)Se2 was shown to improve the efficiency for wide and low band gap solar cells. We study low band gap industrial Cu(In,Ga)(S,Se)2 absorbers, substituting less than 10% of the copper with…
We present a multiscale approach for modeling an intermediate-band solar cell based on a GaAs-GaAlAs quantum dot superlattice of cubic symmetry. Our framework combines high-accuracy theoretical calculations of the superlattice band…
Electronic structure calculations within screened-exchange hybrid density functional theory show that Cu(In,Ga) antisites in both CuInSe2 and CuGaSe2 are localized hole traps, which can be attributed to the experimentally observed N2 level.…
Insulating FeGa$_3$ poses peculiar puzzles beyond the occurrence of an electronic gap in an intermetallic compound. This Fe-based material has a very distinctive structural characteristic with the Fe atoms occurring in dimers. The…
We report optical spectroscopic measurements on electron- and hole-doped BaFe2As2. We show that the compounds in the normal state are not simple metals. The optical conductivity spectra contain, in addition to the free carrier response at…
Traditional CdS buffer layer in selenium-free Cu(In,Ga)S2 solar cells leads to reduced open-circuit voltage because of a negative conduction band offset at the Cu(In,Ga)S2/CdS interface. Reducing this loss necessitates the substitution of…
Boron (B) has the potential for generating an intermediate band in cubic silicon carbide (3C-SiC), turning this material into a highly efficient absorber for single-junction solar cells. The formation of a delocalized band demands high…