Zobrazeno 1 - 10
of 399
pro vyhledávání: '"Ossicini, Stefano"'
The electronic properties of hydrogenated, spherical, Si/Ge and Ge/Si core-shell nanocrystals with a diameter ranging from 1.8 to 4.0 nm are studied within Density Functional Theory. Effects induced by quantum confinement and strain on the near-band-
Externí odkaz:
http://arxiv.org/abs/2206.11058
Publikováno v:
Physics Status Solidi C, 14, 1700193 (2017)
First-principles calculations of work function tuning induced by different chemical terminations on Si(100) surface are presented and discussed. We find that the presence of halogen atoms (I, Br, Cl, and F) leads to an increase of the work function i
Externí odkaz:
http://arxiv.org/abs/1809.08010
Publikováno v:
physica status solidi C 14, 1700198 (2017)
Carrier multiplication is a non-radiative recombination mechanism that leads to the generation of two or more electron-hole pairs after absorption of a single photon. By reducing the occurrence of dissipative effects, this process can be exploited to
Externí odkaz:
http://arxiv.org/abs/1809.07717
Autor:
Marri, Ivan, Ossicini, Stefano
Publikováno v:
AIP Conference Proceedings 1990, 020002 (2018)
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 separated qua
Externí odkaz:
http://arxiv.org/abs/1809.07548
Publikováno v:
Progress in Surface Science, Volume 92, Issue 4, December 2017, Pages 375-408
Si nanocrystals have been extensively studied because of their novel properties and their potential applications in electronic, optoelectronic, photovoltaic, thermoelectric and biological devices. These new properties are achieved through the combina
Externí odkaz:
http://arxiv.org/abs/1807.05304
Autor:
Garcia-Castello, Nuria, Illera, Sergio, Prades, Joan Daniel, Ossicini, Stefano, Cirera, Albert, Guerra, Roberto
Publikováno v:
Nanoscale 7, 12564 (2015)
In the present theoretical work we have considered impurities, either boron or phosphorous, located at different substitutional sites in silicon quantum dots (Si-QDs) with diameters around 1.5\,nm, embedded in a SiO2 matrix. Formation energy calculat
Externí odkaz:
http://arxiv.org/abs/1512.00255
Autor:
Guerra, Roberto, Ossicini, Stefano
Publikováno v:
Journal of American Chemical Society 2014, 136, 4404-4409
In this work we aim at understanding the effect of n-type and p-type substitutional doping in the case of matrix-embedded and freestanding Si nanocrystals. By means of ab-initio calculations we identify the preferential positioning of the dopants and
Externí odkaz:
http://arxiv.org/abs/1505.07351
Autor:
Guerra, Roberto, Ossicini, Stefano
Publikováno v:
Physical Review B 87, 165441 (2013)
The possibility of controlling the optical transition probability between neighbouring silicon nanoclusters (Si-NCs) constitutes nowadays an attractive prospect in nanophotonics and photovoltaics. In this work, by means of theoretical ab-initio calcu
Externí odkaz:
http://arxiv.org/abs/1306.2787
Publikováno v:
Journal of Applied Physics 113, 143505 (2013)
We report on the possibility of describing the absorption and emission characteristics of an ensemble of silicon nanocrystals (NCs) with realistic distributions in the NC size, by the sum of the reponses of the single NCs. The individual NC responses
Externí odkaz:
http://arxiv.org/abs/1306.2785
Publikováno v:
Nature Photonics 6 672-679 (2012)
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 between nan
Externí odkaz:
http://arxiv.org/abs/1306.1856