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Determination of refractive index of various materials on Brewster angle  [PDF]
Eugene A. Tikhonov
Physics , 2015,
Abstract: Studied experimentally the origin of the non-zero reflection of p-polarized radiation (TM) of Brewster's angle. The results have shown the residual reflected light in the vicinity of Brewster angle occurs due to inaccessibility 100% polarization degree the incident linearly-polarized radiation and installation of the zero azimuthal angle. These factors create the s-component of the radiation reflected from the examined surface indeed. A smooth change of reflected light polarization in the vicinity of Brewster angle in the sequence p-s-p appears due to the changing power proportion of reflected p-, and s-components but not is the result of the atomically thin transitional layer at the border of the material/environment according to Drude model. Metrological aspects of refractive index measurement by Brewster angle are investigated: due to the above-mentioned factors, as well as due to the contribution of the reflected scattered light caused by on residual roughness of the optical surface. Advantages of Brewster refractometry for any materials and films without restrictions on the topology of samples and their light scattering and absorption are demonstrated
Refractive index of nanoscale thickness films measured by Brewster refractometry  [PDF]
E. A. Tikhonov,A. K. Lyamets,Yu. V. Malyukin
Physics , 2015,
Abstract: It is shown that reflective laser refractometery at Brewster angle can be usefull for precision measurements of refractive indexes (RI) in the transparency band of various films of nanoscale thickness. The RI measurements of nanoscale porous film on the basis of gadolinium orthosilicate and quartz have been carried out as first experience. It is shown that surface light scattering in such films that is connected with clustering of nanoscale pores can decrease the accuracy of the RI measurements at Brewster angle. Estimated physical dependence RI stipulated by the film thickness reduction (3D-2D transition) in the range of (20-160)nm has not been not detected.
Characterizing the reflectance near the Brewster angle: a Pade-approximant approach  [PDF]
Teresa Yonte,Luis L. Sanchez-Soto
Physics , 2006, DOI: 10.1364/JOSAA.23.003223
Abstract: We characterize the reflectance peak near the Brewster angle for both an interface between two dielectric media and a single slab. To approach this problem analytically, we approximate the reflectance by a first-order diagonal Pad\'e. In this way, we calculate the width and the skewness of the peak and we show that, although they present a well-resolved maximum, they are otherwise not so markedly dependent on the refractive index.
Brewster cross-polarization  [PDF]
A. Aiello,M. Merano,J. P. Woerdman
Physics , 2009, DOI: 10.1364/OL.34.001207
Abstract: We theoretically derive the polarization-resolved intensity distribution of a $TM$-polarized fundamental Gaussian beam reflected by an air-glass plane interface at Brewster incidence. The reflected beam has both a dominant ($TM$) and a cross-polarized ($TE$) component, carried by a $\text{TEM}_{10}$ and a $\text{TEM}_{01}$ Hermite-Gaussian spatial mode, respectively. Remarkably, we find that the $TE$-mode power scales quadratically with the angular spread of the incident beam and it is comparable to the $TM$-mode power. Experimental confirmations of the theoretical results are also presented.
Surface relief resonant Brewster filters with multiple channels

Ma Jian-Yong,Liu Shi-Jie,Zhang Da-Wei,Yao Jian-Ke,Xu Cheng,Jin Yun-Xi,Shao Jian-Da,Fan Zheng-Xiu,

中国物理 B , 2008,
Abstract: In this paper, a new type of resonant Brewster filters (RBF) with surface relief structure for the multiple channels is first presented by using the rigorous coupled-wave analysis and the $S$-matrix method. By tuning the depth of homogeneous layer which is under the surface relief structure, the multiple channels phenomenon is obtained. Long range, extremely low sidebands and multiple channels are found when the RBF with surface relief structure is illuminated with Transverse Magnetic incident polarization light near the Brewster angle calculated with the effective media theory of sub wavelength grating. Moreover, the wavelengths of RBF with surface relief structure can be easily shifted by changing the depth of homogeneous layer while its optical properties such as low sideband reflection and narrow band are not spoiled when the depth is changed. Furthermore, the variation of the grating thickness does not effectively change the resonant wavelength of RBF, but have a remarkable effect on its line width, which is very useful for designing such filters with different line widths at desired wavelength.
Effect of Effective Refractive Index of Grating in FBG Splitter
International Journal of Engineering Science and Technology , 2011,
Abstract: The Fiber Bragg Gratings have been used extensively in the communication industry. Fiber Bragg grating is written directly into the core of the optical fiber and it is quite an attractive technique for wavelength splitter since it provides high reflectivity at a certain wavelength, with negligible transmission losses for others, providing a wavelength-channel selection with low crosstalk between adjacent channels.In this paper we propose a Fiber Bragg Grating base splitter with alteration of effective refractive index of grating for Ethernet passive optical network. With the increase in the effective refractive index the reflectivity of grating is increased. We analysed the effect of effective refractive index on reflectivity of grating. In our work the Bragg wavelength has been fixed at 1550 nm,length of the grating as 10mm and with effective refractive index as 4.0 it has been found that the reflectivity of the grating or the effectiveness of the grating in extracting the wavelength is 92-93%.
Fresnel Formulate and Brewster Law of Optical Waves in the Left-handed Materials

Tian Xiulao,

光子学报 , 2006,
Abstract: Universal Fresnel formulae at the interface of two medium whose permitivity and permeability are ε1μ1、ε2μ2 are derived from Maxwell theory. The universal Fresnel formulae of the reflectivity and transmission coefficients are given. It is applicable for Right-handed materials and Left-handed materials.Analyzing properties of refection and refraction between two medium,the condition of Brewster angle are given in the Left-handed materials. The condition show that Brewster angle is not only relate to refractive index but also relate to permeability.
Studying of refractive index measurements in reflected light  [PDF]
E. A. Tikhonov,V. A. Ivashkin
Physics , 2010,
Abstract: Two methods of refractometry in reflected light from optical surface of samples are considered and studied experimentally. Methods are grounded on results of Fresnel theory of concerning light reflectivity at near normal incidence and Brewster angle. Sources of errors for both methods were considered and possibility of measuring of the refractive index with application of laser radiation with accuracy to within 4th sign was shown. Advantages of described methods concerning requirements to preparation of samples to refractive index measurement of solid, thin-film and absorbing materials are scored.
Generalized Brewster-Kerker effect in dielectric metasurfaces  [PDF]
Ramon Paniagua-Dominguez,Ye Feng Yu,Andrey E. Miroschnichenko,Leonid A. Krivitsky,Yuan Hsing Fu,Vytautas Valuckas,Leonard Gonzaga,Yeow Teck Toh,Anthony Yew Seng Kay,Boris Luk'yanchuk,Arseniy I. Kuznetsov
Physics , 2015,
Abstract: Polarization is one of the key properties defining the state of light. It was discovered in the early 19th century by Brewster, among others, while studying light reflected from materials at different angles. These studies led to the first polarizers, based on Brewster's effect. One of the most active trends in photonics now is devoted to the study of miniaturized, sub-wavelength devices exhibiting similar, or even improved, functionalities compared to those achieved with bulk optical elements. In the present work, it is theoretically predicted that a properly designed all-dielectric metasurface exhibits a generalized Brewster effect potentially for any angle, wavelength and polarization of choice. The effect is experimentally demonstrated for an array of silicon nanodisks at visible wavelengths. The underlying physics of this effect can be understood in terms of the suppressed scattering at certain angles that results from the interference between the electric and magnetic dipole resonances excited in the nanoparticles, predicted by Kerker in early 80s. This reveals deep connection of Kerker's and Brewster's legacies and opens doors for Brewster phenomenon to new applications in photonics, which are not bonded to a specific polarization or angle of incidence.
Characterization of Long-period Grating Refractive Index Sensors and Their Applications  [PDF]
Hiroshi Tsuda,Kei Urabe
Sensors , 2009, DOI: 10.3390/s90604559
Abstract: The influence of grating length and bend radius of long-period gratings (LPGs) on refractive index sensing was examined. Sensitivity to refractive indexes smaller than that of silica could be enhanced by bending LPGs. Bent LPGs lost sensitivity to refractive indexes higher than that of silica, whereas a 20-mm-long LPG arranged in a straight line had considerable sensitivity. These experimental results demonstrated that the sensitivity characteristics of LPGs to refractive index could be controlled by grating length and bend radius.
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