Enhancement of the Spontaneous Emission Rates in all Porous Silicon Optical Microcavities

1996 ◽  
Vol 452 ◽  
Author(s):  
L. Pavesi ◽  
M. Cazzanelli ◽  
O. Bisi
Keyword(s):  
Porous Silicon ◽  
Spontaneous Emission ◽  
Silicon Layer ◽  
Porous Silicon Layer ◽  
Emission Rates ◽  
Time Resolved ◽  
Optical Microcavities ◽  
Fabry Perot ◽  
Optical Modes ◽  
Time Resolved Photoluminescence

AbstractThe emission properties of a porous silicon layer placed in an optical microcavity is investigated by photoluminescence and time resolved photoluminescence measurements. The microcavity is formed by an all porous silicon Fabry-Perot filter made by two distributed Bragg reflectors separated by a λ or λ/2 porous silicon layer. Our main findings are that the spontaneous emission spectrum is drastically modified: the linewidth is narrowed, the time decay of the emission is shortened by a factor of about 2/3 at room temperature and the peak emission intensity is increased by a factor of more than 10. These facts are caused by the redistribution of the optical modes in the microcavity due to the presence of the optical resonator and to the variation of the dielectric environment.

White Light Luminescence from Nano-ZnS Doped Porous Silicon

2001 ◽  
Vol 686 ◽  
Author(s):  
K. W. Cheah ◽  
Ling Xu ◽  
Xinfan Huang
Keyword(s):  
Porous Silicon ◽  
White Light ◽  
Radiative Recombination ◽  
Surface States ◽  
Silicon Layer ◽  
Visible Spectrum ◽  
Porous Silicon Layer ◽  
Time Resolved ◽  
Direct Excitation ◽  
Time Resolved Photoluminescence

Nano-ZnS was deposited into porous silicon. By varying the concentration of Zn2+ ion solution during nano-ZnS formation, the amount of nano-ZnS in porous silicon host can be controlled. The doped porous silicon exhibited a gradual shift in its photoluminescence peak from red to blue as a function of the nano-ZnS coverage. At an optimum doping, white light photoluminescence was obtained. A study in the luminescence lifetime showed that the radiative recombination at the blue end of the visible spectrum was due to nano-ZnS, whereas, luminescence emission at the red end of the visible spectrum came from porous silicon. The latter luminescence was due to in part tunneling of excited electrons from nanoZnS into porous silicon and in part direct excitation of porous silicon layer. Time-resolved photoluminescence also showed that radiative recombination was effectively dominated by the nano-ZnS. Photoluminescence excitation result revealed the presence of two excitation levels; one belonged to nano-ZnS at near uv region, and another at about 520 nm from the surface states of porous silicon and nano-ZnS. The doping of nano-ZnS into porous silicon demonstrates that luminescence color tuning is possible when an appropriate functional material is introduced into porous silicon.

Effect of the Porous Silicon Layer Structure on Gas Adsorption

2020 ◽  
Vol 12 (4) ◽  
pp. 04020-1-04020-5
Author(s):  
A. P. Oksanich ◽  
◽  
S. E. Pritchin ◽  
M. A. Mashchenko ◽  
A. Yu. Bobryshev ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Gas Adsorption ◽  
Layer Structure ◽  
Silicon Layer ◽  
Porous Silicon Layer

scholarly journals Morphology and FT IR spectra of porous silicon

2017 ◽  
Vol 68 (7) ◽  
pp. 53-57 ◽  
Author(s):  
Martin Kopani ◽  
Milan Mikula ◽  
Daniel Kosnac ◽  
Jan Gregus ◽  
Emil Pincik
Keyword(s):  
Porous Silicon ◽  
Ir Spectra ◽  
Silicon Layer ◽  
Porous Silicon Layer ◽  
Layer Formation ◽  
Porous Si ◽  
Ft Ir ◽  
P Type ◽  
Type Sample ◽  
Ftir Investigation

AbstractThe morphology and chemical bods of p-type and n-type porous Si was compared. The surface of n-type sample is smooth, homogenous without any features. The surface of p-type sample reveals micrometer-sized islands. FTIR investigation reveals various distribution of SiOxHycomplexes in both p-and n-type samples. From the conditions leading to porous silicon layer formation (the presence of holes) we suggest both SiOxHyand SiFxHycomplexes in the layer.

Sensing mechanism analysis on one-dimensional photonic crystal with air slot-porous silicon-air slot F–P cavity

2019 ◽  
Vol 33 (13) ◽  
pp. 1950159 ◽  
Author(s):  
Ying Chen ◽  
Xinbei Gao ◽  
Pei Luo ◽  
Yangmei Xu ◽  
Jinggang Cao ◽  
...  
Keyword(s):  
Refractive Index ◽  
Photonic Crystal ◽  
Porous Silicon ◽  
Structural Parameters ◽  
Silicon Layer ◽  
Porous Silicon Layer ◽  
Resonant Peak ◽  
Mechanism Analysis ◽  
Q Value ◽  
Quality Factor Q

Based on the evanescent wave resonance, a photonic crystal sensing structure with air slot-porous silicon-air slot Fabry–Perot cavity (F–P cavity) is proposed. Taking the F–P cavity as the sensing unit, when the gas to be detected is filled into the sensing unit, the refractive index of the air slot will be changed and the refractive index of the porous silicon layer will also be varied, both of which will shift the resonant peak and greatly increase the sensitivity of the sensor. By adjusting the structural parameters, the quality factor (Q value) can be optimized. A model for the relationship between the resonant wavelength and the refractive index of the detected organic gas was established, and the refractive index sensing performance was analyzed. The results show that the Q value of the structure can attain to 12312.2 and the sensitivity is about 8661.708 nm/RIU, which can provide effective theoretical reference and technical guidance for organic gas detection with low concentration.

Sign in / Sign up

Export Citation Format

Share Document