Performance evaluation of IEEE 802.15.7 CSK modulation under blue shift effect of optical receiver filters

In the present paper, we have investigated structural, optical as well as electronic properties of electron beam evaporated Ge thin films having layer thicknesses ranging from ultra-thin (5 nm) to thick (200 nm). The Raman spectra show that all peaks are shifted towards lower wave number as compared to their bulk counterparts and are considered as a signature of nanostructure formation and quantum confinement effect. The Raman line exhibits transformation from nanocrystalline to microcrystalline phase with a reduction in blue shift of peak position with increase in Ge film thickness (>5 nm). Similarly, the optical absorption spectra corresponding to these films also show reduction in blue shift effect, although Ge 5 nm film shows the absorption behaviour quite different from higher thickness films. The corresponding band gap values obtained from absorption measurements are much larger than bulk Ge and are mainly attributed to the effect of quantum confinement as expected for small size particles calculated from GIXRD patterns. AFM data in each case are correlated and discussed with structural as well as optical results to support the effect of growth morphology on the above-mentioned observations. The results are further supported by photoelectron spectroscopy (PES), photoluminescence (PL) and resistivity measurements and are interpreted in terms of crystallinity and quantum confinement effect.

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Moment generating function of superlattice avalanche photodiodes as a basis for accurate optical receiver performance evaluation

IEE Proceedings J Optoelectronics ◽

10.1049/ip-j.1989.0022 ◽

1989 ◽

Vol 136 (2) ◽

pp. 118

Author(s):

R.S. Fyath ◽

J.J. O'Reilly

Keyword(s):

Performance Evaluation ◽

Generating Function ◽

Avalanche Photodiodes ◽

Moment Generating Function ◽

Optical Receiver ◽

Receiver Performance

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The blue-shift effect of the ion-milling-formed HgCdTe photodiodes

10.1117/12.792273 ◽

2008 ◽

Cited By ~ 1

Author(s):

F. X. Zha ◽

J. Shao

Keyword(s):

Blue Shift ◽

Ion Milling ◽

Shift Effect ◽

Hgcdte Photodiodes

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Research on Syntheses and Properties of Water-soluble Symmetrical Squarylium Double-cyanine Dyes

The Open Materials Science Journal ◽

10.2174/1874088x01509010113 ◽

2015 ◽

Vol 9 (1) ◽

pp. 113-118

Author(s):

Xinding Yao ◽

Ruina Fang ◽

Hongjian Pang ◽

Guoji Liu

Keyword(s):

Raw Materials ◽

Stokes Shift ◽

Blue Shift ◽

Cyanine Dyes ◽

Water Soluble ◽

Cyanine Dye ◽

Squaric Acid ◽

Diethyl Ester ◽

Shift Effect ◽

Photo Stability

In this paper, 2,3,3-trimethyl-3H-indolin was synthesized by phenylhydrazine and 3-methyl-2-butanone as raw materials in the acetic acid reacted with different nitrogenalkylating reagents. Semi mono-cyanine dye and semi dicyanine dye were prepared with the help of squaric acid diethyl ester. The spectral properties of the target products were checked. The results show that compared with symmetrical squarylium mono-indocyanine dyes with the same substituent, the photo-stability of the bi-cyanine dyes were much better. When dissolved in water, the dye showed shorter maximum absorption wavelength, shorter maximum emission wavelength and shorter Stokes shift and apparent aggregation. In protic solvents, dye spectra showed a blue shift effect with an increase of solution polarity, while in aprotic solvents, dye spectrum showed a red shift with solution polarity increased. Among different solvents, the photostability of the dye in methanol is strongest.

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