Interaction of Gaussian beams with a conducting finite grating: reflection case

AbstractWe dispersed electrochemically etched Si into ultrabright ultrasmall nanoparticles, with brightness higher than fluorescein or rhodamine. The emission from single particles is readily detectable. Aggregates or films of the particles exhibit emission with highly nonlinear characteristics. We observe directed blue beams at ∼ 410 nm between faces of aggregates excited by femtosecond radiation at 780 nm; and at ∼ 610 nm from aggregates of red luminescent Si nanoparticles excited by radiation at 550-570 nm from a mercury lamp. Intense directed Gaussian beams, a pumping threshold, spectral line narrowing, and speckle patterns manifest the emission. The results are analyzed in terms of population inversion and stimulated emission in quantum confinement-induced Si-Si dimer phase, found only on ultrasmall Si nanoparticles. This microlasing constitutes an important step towards the realization of a laser on a chip.

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Scintillation index of flat-topped Gaussian beams

Applied Optics ◽

10.1364/ao.45.003793 ◽

2006 ◽

Vol 45 (16) ◽

pp. 3793 ◽

Cited By ~ 109

Author(s):

Yahya Baykal ◽

Halil T. Eyyuboğlu

Keyword(s):

Scintillation Index ◽

Gaussian Beams

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Propagation of chirped sinh-Gaussian beams in uniaxial crystals orthogonal to the optical axis

Optical and Quantum Electronics ◽

10.1007/s11082-021-03184-4 ◽

2021 ◽

Vol 53 (9) ◽

Author(s):

Mert Bayraktar

Keyword(s):

Optical Axis ◽

Gaussian Beams

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Paraxial Propagation Properties of Radially Polarized Odd‐Pearcey Gaussian Beams in Free Space

Annalen der Physik ◽

10.1002/andp.202100055 ◽

2021 ◽

pp. 2100055

Author(s):

Mingyue Fang ◽

Xiang Liao ◽

Jiajia Zhao ◽

Chuangjie Xu ◽

Yixiao Zhang ◽

...

Keyword(s):

Free Space ◽

Gaussian Beams ◽

Propagation Properties ◽

Radially Polarized

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OAM light propagation through tissue

Scientific Reports ◽

10.1038/s41598-021-82033-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Netanel Biton ◽

Judy Kupferman ◽

Shlomi Arnon

Keyword(s):

Light Propagation ◽

Biological Imaging ◽

Gaussian Beams ◽

Medical Implants ◽

Optical Wireless ◽

Scattering Media ◽

Valuable Contribution ◽

Light Beams ◽

First Time ◽

Diffuse Media

AbstractA major challenge in use of the optical spectrum for communication and imaging applications is the scattering of light as it passes through diffuse media. Recent studies indicate that light beams with orbital angular momentum (OAM) can penetrate deeper through diffuse media than simple Gaussian beams. To the best knowledge of the authors, in this paper we describe for the first time an experiment examining transmission of OAM beams through biological tissue with thickness of up to a few centimeters, and for OAM modes reaching up to 20. Our results indicate that OAM beams do indeed show a higher transmittance relative to Gaussian beams, and that the greater the OAM, the higher the transmittance also up to 20, Our results extend measured results to highly multi scattering media and indicate that at 2.6 cm tissue thickness for OAM of order 20, we measure nearly 30% more power in comparison to a Gaussian beam. In addition, we develop a mathematical model describing the improved permeability. This work shows that OAM beams can be a valuable contribution to optical wireless communication (OWC) for medical implants, optical biological imaging, as well as recent innovative applications of medical diagnosis.

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