Room Temperature Light Induced Electron Spin Resonauce In Undoped Hydrogenated Amorphous Silicon (a-Si:H)

1986 ◽  
Vol 70 ◽  
Author(s):  
R. Pandya ◽  
S. Zafar ◽  
E. A. Schiff
Keyword(s):  
Electron Spin ◽  
Room Temperature ◽  
Small Shift ◽  
Hydrogenated Silicon ◽  
Transient Photocurrent ◽  
Amorphous Hydrogenated Silicon ◽  
Spin Resonance ◽  
Absorption Studies ◽  
G Value ◽  
Hydrogenated Amorphous

ABSTRACTThe effects of illumination upon the absorption electron spin resonance spectrum of the dangling bond defect system have been studied in undoped amorphous hydrogenated silicon (a-Si:H). A small shift of the inhomogeneous envelope of the system towards higher g-value is observed at roomtemperature. The shift is not accompanied by a significant change in the signal. Results are reported which indicate that this shift is not due to illumination induced heating of the specimen or calibration changes of the spectrometer. The results may be related to previously reported optical bias effects upon transient photocurrent and photoinduced absorption studies.

Efficient Visible Room Temperature Photoluminescence in Wide Gap Hydrogenated Amorphous Silicon-Carbon Alloys

1994 ◽  
Vol 336 ◽  
Author(s):  
Leandro R. Tessler ◽  
Ionel Solomon
Keyword(s):  
Room Temperature ◽  
Urbach Energy ◽  
Photoluminescence Intensity ◽  
Tetrahedral Coordination ◽  
Hydrogenated Silicon ◽  
Amorphous Hydrogenated Silicon ◽  
Silicon Carbon ◽  
Hydrogenated Amorphous ◽  
Carbon Concentrations ◽  
Phonon Model

ABSTRACTWe report a photoluminescence study on amorphous hydrogenated silicon carbon (a-Si1-xCx:H) alloys with carbon concentration in the range O < x < 0.5, prepared by PECVD in the “low-power” regime, that preserves the tetrahedral coordination of the carbon atoms. These samples have optical gaps higher than conventional “high power” alloys with the same carbon content. For carbon concentrations below x = 0.2 the photoluminescence behaves essentially as in pure a-Si:H with increased gap, Urbach energy and DOS. For higher carbon concentrations there is a change in the recombination process, that we attribute to a change in the dominating diffusion process of the photogenerated carriers. The integrated photoluminescence intensity for carbon-rich samples is very weakly dependent on the temperature, and at room temperature it approaches that of pure a-Si:H at 77K. For all samples, the photoluminescence bandwidth can be well described by a zero-phonon model.

Porous Silicon from Hydrogenated Amorphous Silicon: Comparison with Crystalline Porous Silicon

1996 ◽  
Vol 452 ◽  
Author(s):  
J.-N. Chazalviel ◽  
R. B. Wehrspohn ◽  
I. Solomon ◽  
F. Ozanam
Keyword(s):  
Porous Silicon ◽  
Room Temperature ◽  
Quantum Confinement Effect ◽  
Confinement Effect ◽  
High Resistivity ◽  
Hydrogenated Silicon ◽  
Boron Doped ◽  
Amorphous Hydrogenated Silicon ◽  
Recombination Centers ◽  
Hydrogenated Amorphous

AbstractDevice-grade, boron-doped amorphous hydrogenated silicon can be made microporous by anodization in ethanoic HF. The thickness of the porous layer is limited by an instability due to the high resistivity of the material. Amorphous porous silicon exhibits strong room-temperature photoluminescence around 1.5 eV even in samples containing a high density of non-radiative recombination centers. This demonstrates the presence of a spatial confinement effect, as opposed to quantum confinement effect for crystalline porous silicon. The temperature dependence of the luminescence intensity is also accounted for on the same grounds.

MICROWAVE ABSORPTION STUDIES ON HIGH-Tc SUPERCONDUCTORS AND RELATED MATERIALS III: Electron Spin Resonance Studies of Y2Ba1Cu1O5 and Gd2Ba1Cu1O5

1991 ◽  
Vol 05 (13) ◽  
pp. 895-901 ◽  
Author(s):  
K. SUGAWARA ◽  
D. J. BAAR ◽  
Y. SHIOHARA ◽  
S. TANAKA
Keyword(s):  
Electron Spin Resonance ◽  
Microwave Absorption ◽  
Electron Spin ◽  
Room Temperature ◽  
Magnetic Ordering ◽  
High Tc Superconductors ◽  
Néel Temperature ◽  
High Tc ◽  
Spin Resonance ◽  
Absorption Studies

The ESR of Cu 2+ and Gd 3+ ion in Y 2 Ba 1 Cu 1 O 5 and Gd 2 Ba 1 Cu 1 O 5 has been studied at temperatures from 4 K to room temperature. Particular emphasis has been paid to the ESR linewidths (∆H PP ) and g-values of the ions. The ∆H PP and g-values for Y 2 Ba 1 Cu 1 O 5 were found to have anomalous increments near 15 K, close to the Néel temperature of Y 2 Ba 1 Cu 1 O 5. Similarly, ∆H PP for Gd 2 Ba 1 Cu 1 O 5 had peaks near 12 K. Our analysis reveals that the ESR signal from Gd 2 Ba 1 Cu 1 O 5 is dominated by the Gd 3+ ESR. However, the magnetic ordering may be caused by both Gd-Gd and Gd-Cu interactions.

scholarly journals Force detection of high-frequency electron spin resonance near room temperature using high-power millimeter-wave source gyrotron

2021 ◽  
Vol 118 (2) ◽  
pp. 022407
Author(s):  
Hideyuki Takahashi ◽  
Yuya Ishikawa ◽  
Tsubasa Okamoto ◽  
Daiki Hachiya ◽  
Kazuki Dono ◽  
...  
Keyword(s):  
Electron Spin Resonance ◽  
Millimeter Wave ◽  
Electron Spin ◽  
High Power ◽  
High Frequency ◽  
Room Temperature ◽  
Force Detection ◽  
Wave Source ◽  
Spin Resonance ◽  
Millimeter Wave Source
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