scholarly journals Free electron-driven photophysics in n-type doped silicon nanocrystals

Nanoscale ◽  
2018 ◽  
Vol 10 (25) ◽  
pp. 12068-12077 ◽  
Author(s):  
R. Limpens ◽  
N. R. Neale
Keyword(s):  
Free Electron ◽  
Silicon Nanocrystals ◽  
Spectroscopic Techniques ◽  
Comprehensive Understanding ◽  
Si Nanocrystals ◽  
Doped Silicon

By making use of multiple spectroscopic techniques we provide a comprehensive understanding of the photophysics of n-type doped Si nanocrystals.

scholarly journals Ab initio studies of the optoelectronic structure of undoped and doped silicon nanocrystals and nanowires: the role of size, passivation, symmetry and phase

2020 ◽  
Vol 222 ◽  
pp. 217-239 ◽  
Author(s):  
Stefano Ossicini ◽  
Ivan Marri ◽  
Michele Amato ◽  
Maurizia Palummo ◽  
Enric Canadell ◽  
...  
Keyword(s):  
Ab Initio ◽  
Silicon Nanocrystals ◽  
Si Nanocrystals ◽  
Doped Silicon ◽  
Co Doped

Results from ab initio calculations for singly- and co- doped Si nanocrystals and nanowires are presented.

Laser Induced Etching for Generation of Si Nanocrystals and Spectroscopic Investigation of Morphology

2005 ◽  
Vol 23 ◽  
pp. 43-46
Author(s):  
H.S. Mavi ◽  
S. Rath ◽  
Arun Shukla
Keyword(s):  
Quantum Confinement ◽  
Silicon Nanocrystals ◽  
Laser Wavelength ◽  
Interconnected Network ◽  
Substrate Type ◽  
Argon Ion Laser ◽  
Si Nanocrystals ◽  
Ion Laser ◽  
Laser Induced Etching ◽  
Argon Ion

Laser-induced etching of silicon is used to generate silicon nanocrystals. The pore structure depends on the substrate type and etching laser wavelength. Porous silicon (PS) samples prepared by Nd:YAG laser (1.16 eV) etching of n-type substrate showed a fairly uniform and highly interconnected network of nearly circular pores separated by thin columnar boundaries, while no circular pits were produced by argon- ion laser (2.41 eV) etching under similar conditions. The size and size distribution of the nanocrystals are investigated by Raman and photoluminescence spectroscopies and analyzed within the framework of quantum confinement models.

Comparative Optical Studies of Chemically Synthesized Silicon Nanocrystals

1996 ◽  
Vol 452 ◽  
Author(s):  
Gildardo R. Delgado ◽  
Howard W.H. Lee ◽  
Susan M. Kauzlarich ◽  
Richard A. Bley
Keyword(s):  
Porous Silicon ◽  
Silicon Nanocrystals ◽  
Surface Passivation ◽  
Theoretical Calculations ◽  
Dominant Role ◽  
Blue Emission ◽  
Surface States ◽  
Si Nanocrystals ◽  
Optical And Electronic Properties ◽  
Passivation Layers

AbstractWe studied the optical and electronic properties of silicon nanocrystals derived from two distinct fabrication procedures. One technique uses a controlled chemical reaction. In the other case, silicon nanocrystals are produced by ultrasonic fracturing of porous silicon layers. We report on the photoluminescence, photoluminescence excitation, and absorption spectroscopy of various size distributions derived from these techniques. We compare the different optical properties of silicon nanocrystals made this way and contrast them with that observed in porous silicon. Our results emphasize the dominant role of surface states in these systems as manifested by the different surface passivation layers present in these different fabrication techniques. Experimental absorption measurements are compared to theoretical calculations with good agreement. Our results provide compelling evidence for quantum confinement in both types of Si nanocrystals. Our results also indicate that the blue emission from very small Si nanocrystals corresponds to the bandedge emission, while the red emission arises from traps.

The Oxidation Behavior of Silicon Nanocrystals in the Submonolayer Region

1997 ◽  
Vol 486 ◽  
Author(s):  
J. Diener ◽  
M. Ben-Chorin ◽  
D. I. Kovalev ◽  
G. Polisski ◽  
F. Koch
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Porous Silicon ◽  
Silicon Nanocrystals ◽  
Oxidation Behavior ◽  
Surface Oxidation ◽  
Square Root ◽  
Mesoporous Silicon ◽  
Si Nanocrystals ◽  
Evolution Of Oxygen

AbstractFourier transform infrared spectroscopy is used to determine the time evolution of oxygen incorporation onto the surface of silicon nanocrystals. Oxygen concentrations up to one monolayer are investigated. The temporal progress of surface oxidation of Si nanocrystals in porous silicon shows a linear dependence on the square root of the oxidation time. This is similar to the oxidation of bulk Si and mesoporous silicon.

Radiation spectrum of hot excitons in Si nanocrystals

2016 ◽  
Vol 55 (4) ◽  
Author(s):  
Anton V. Gert ◽  
Irina N. Yassievich
Keyword(s):  
Energy Distribution ◽  
Silicon Nanocrystals ◽  
Energy Exchange ◽  
Relaxation Times ◽  
Exciton State ◽  
Time Interval ◽  
Pump Probe ◽  
Si Nanocrystals ◽  
Wide Energy ◽  
Probe Spectroscopy

The self-trapped exciton state (STE) is very important for the dynamics of hot excitons in photoexcited silicon nanocrystals embedded in a SiO2 matrix. This fact has been recently confirmed by the experimental data obtained by the femtosecond pump– probe spectroscopy technique in Amsterdam University. In this work we have studied the energy exchange between the exciton localized in the STE state and the hot exciton in the core of silicon nanocrystals and have shown that it determines the dynamics of the energy distribution of the hot excitons. Using the Monte-Carlo we have simulated the energy distribution of excitons in the time interval 10–100 ps after excitation. Thus the model of formation of the distribution of hot excitons in silicon nanocrystals is developed and the fast formation of the wide energy distribution is demonstrated. The form of the photoluminescence spectrum almost directly corresponds to the energy distribution of excitons in a silicon nanocrystal at a given moment. In the result we have found the relaxation times of hot excitons equal to 100 ps and the inner quantum efficiency of the ultrafast photoluminescence of about 0.1%. These values are close to the experimentally observed ones.

Doped silicon nanocrystals from organic dopant precursor by a SiCl4-based high frequency nonthermal plasma

2014 ◽  
Vol 105 (18) ◽  
pp. 183110 ◽  
Author(s):  
Shu Zhou ◽  
Yi Ding ◽  
Xiaodong Pi ◽  
Tomohiro Nozaki
Keyword(s):  
High Frequency ◽  
Silicon Nanocrystals ◽  
Nonthermal Plasma ◽  
Doped Silicon ◽  
Dopant Precursor

Technology and characterization of MIS structures with co-doped silicon nanocrystals (Si-NCs) embedded in hafnium oxide (HfOx) ultra-thin layers

2017 ◽  
Vol 178 ◽  
pp. 298-303 ◽  
Author(s):  
A. Mazurak ◽  
R. Mroczyński ◽  
J. Jasiński ◽  
D. Tanous ◽  
B. Majkusiak ◽  
...  
Keyword(s):  
Hafnium Oxide ◽  
Silicon Nanocrystals ◽  
Thin Layers ◽  
Doped Silicon ◽  
Co Doped ◽  
Mis Structures

Synthesis, optical properties and theoretical modelling of discrete emitting states in doped silicon nanocrystals for bioimaging

Nanoscale ◽  
2018 ◽  
Vol 10 (33) ◽  
pp. 15600-15607 ◽  
Author(s):  
B. F. P. McVey ◽  
D. König ◽  
X. Cheng ◽  
P. B. O'Mara ◽  
P. Seal ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Silicon Nanocrystals ◽  
Theoretical Modelling ◽  
Fundamental Interest ◽  
Doped Silicon ◽  
The Creation

The creation of multiple emission pathways in quantum dots (QDs) is an exciting prospect with fundamental interest and optoelectronic potential.

Design guidelines for transition metals as interstitial emitters in silicon nanocrystals to tune photoluminescence properties: zinc as biocompatible example

Nanoscale ◽  
2020 ◽  
Vol 12 (37) ◽  
pp. 19340-19349
Author(s):  
Dirk König ◽  
Richard D. Tilley ◽  
Sean C. Smith
Keyword(s):  
Medical Imaging ◽  
Transition Metal ◽  
Transition Metals ◽  
Silicon Nanocrystals ◽  
Design Guidelines ◽  
Photoluminescence Properties ◽  
Design Rules ◽  
Doped Silicon ◽  
Metal Doped ◽  
Microwave Excitation

General photoluminescence design rules for interstitial transition-metal-doped silicon nanocrystals are derived; Zn shows excellent properties for medical imaging and plasmonic microwave excitation to exactly eliminate marked cells.

Ab Initio Plasmonics of Externally Doped Silicon Nanocrystals

ACS Photonics ◽  
2019 ◽  
Vol 6 (6) ◽  
pp. 1474-1484 ◽  
Author(s):  
Fabio Della Sala ◽  
Maria Pezzolla ◽  
Stefania D’Agostino ◽  
Eduardo Fabiano
Keyword(s):  
Ab Initio ◽  
Silicon Nanocrystals ◽  
Doped Silicon
Sign in / Sign up

Export Citation Format

Share Document