L. Maksimov, A. Anan’ev, V. Bogdanov, A. Lipovskii, D. Tagantsev, O. Yanush
Inorganic glass is material having nanoscaled physical and chemical inhomogeneities ad initio because glass inherits thermodynamic fluctuations of concentration, density and anisotropy of a glass forming melt. Combining light scattering and high temperature acoustics data allows to use the effect of internal immersion for designing multicomponent glasses with Rayleigh scattering losses lower than those of the silica glass. Non-random spatial distribution of dopants including rare-earth (RE) ions in a glass host (doped ion segregation) causes excessive Rayleigh scattering losses and enhancement of RE ion-ion interaction. Therefore, it opens the way to optimize operation parameters of laser and up-converting glasses by the proper choice of glass host composition. Results of Raman scattering spectra processing and characterization of electrooptical (EO) sensitivity of niobate glasses showed the existence of groups with stoichiometry of the well-known EO crystals and crystal-like orderliness (crystal motifs) in the glasses as the necessary condition of high EO sensitivity. It was found that EO sensitivity of glasses could be essentially increased by thermal treatment.
{"title":"Nanostructure of glasses: experimental evidence","authors":"L. Maksimov, A. Anan’ev, V. Bogdanov, A. Lipovskii, D. Tagantsev, O. Yanush","doi":"10.1117/12.815745","DOIUrl":"https://doi.org/10.1117/12.815745","url":null,"abstract":"Inorganic glass is material having nanoscaled physical and chemical inhomogeneities ad initio because glass inherits thermodynamic fluctuations of concentration, density and anisotropy of a glass forming melt. Combining light scattering and high temperature acoustics data allows to use the effect of internal immersion for designing multicomponent glasses with Rayleigh scattering losses lower than those of the silica glass. Non-random spatial distribution of dopants including rare-earth (RE) ions in a glass host (doped ion segregation) causes excessive Rayleigh scattering losses and enhancement of RE ion-ion interaction. Therefore, it opens the way to optimize operation parameters of laser and up-converting glasses by the proper choice of glass host composition. Results of Raman scattering spectra processing and characterization of electrooptical (EO) sensitivity of niobate glasses showed the existence of groups with stoichiometry of the well-known EO crystals and crystal-like orderliness (crystal motifs) in the glasses as the necessary condition of high EO sensitivity. It was found that EO sensitivity of glasses could be essentially increased by thermal treatment.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133388921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Fomins, M. Reinfelde, A. Larichev, N. Iroshnikov, A. Gerbreders, M. Ozolinsh
Amorphous chalcogenide thin films are excellent materials for holographic recordings. AsSeS thin film coating is a useful optical material for it's thickness to be easily corrected with the use of exposure to light and consecutive chemical etching. Following properties allow to treat the surface of AsSeS chalcogenide films and to use them in adaptive optics systems for correction of the optical wavefront. Hereby, we characterize AsSeS film properties to be used for correction of optical aberrations of the human eye. The thickness of the film is characterized with the method of spectrodensitometry and the surface profile depth with a Hartman- Shack waveform analyzator.
{"title":"Photoinduced AsSeS thin film phase plates as adaptive optics mirrors for eye aberration correction","authors":"S. Fomins, M. Reinfelde, A. Larichev, N. Iroshnikov, A. Gerbreders, M. Ozolinsh","doi":"10.1117/12.815948","DOIUrl":"https://doi.org/10.1117/12.815948","url":null,"abstract":"Amorphous chalcogenide thin films are excellent materials for holographic recordings. AsSeS thin film coating is a useful optical material for it's thickness to be easily corrected with the use of exposure to light and consecutive chemical etching. Following properties allow to treat the surface of AsSeS chalcogenide films and to use them in adaptive optics systems for correction of the optical wavefront. Hereby, we characterize AsSeS film properties to be used for correction of optical aberrations of the human eye. The thickness of the film is characterized with the method of spectrodensitometry and the surface profile depth with a Hartman- Shack waveform analyzator.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116585005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Saito, Yoshinori Takahashi, K. Matsuda, M. Yamazaki, N. Sawanobori
Upconversion characteristics of rare-earth cations were utilized for emitting or controlling visible light with infrared light. A fluorescent glass rod was fabricated by using durable AlF3-based glass that contained high-concentration Er3+ cations. This glass rod acted as a two-way wavelength converter; i.e., visible light (~500 nm) was converted to infrared light (~800 nm) as it passed through the glass, and infrared light that propagated in the opposite direction was converted to visible light. An infrared-responsive photochromic compound was fabricated by dispersing spirobenzopyran and upconversion powder (Gd2O2S:Yb3+Er 3+) in photocurable acrylate. When this compound was exposed to ultraviolet light (~370 nm), a strong absorption band appeared in the visible spectral region due to photochromic isomerization of spirobenzopyran. This absorption band disappeared by irradiation of a 940-nm laser beam, since the upconversion powder emitted green light that caused bleaching of colored spirobenzopyran.
{"title":"Visible light emission and control by infrared-responsive materials","authors":"M. Saito, Yoshinori Takahashi, K. Matsuda, M. Yamazaki, N. Sawanobori","doi":"10.1117/12.815272","DOIUrl":"https://doi.org/10.1117/12.815272","url":null,"abstract":"Upconversion characteristics of rare-earth cations were utilized for emitting or controlling visible light with infrared light. A fluorescent glass rod was fabricated by using durable AlF3-based glass that contained high-concentration Er3+ cations. This glass rod acted as a two-way wavelength converter; i.e., visible light (~500 nm) was converted to infrared light (~800 nm) as it passed through the glass, and infrared light that propagated in the opposite direction was converted to visible light. An infrared-responsive photochromic compound was fabricated by dispersing spirobenzopyran and upconversion powder (Gd2O2S:Yb3+Er 3+) in photocurable acrylate. When this compound was exposed to ultraviolet light (~370 nm), a strong absorption band appeared in the visible spectral region due to photochromic isomerization of spirobenzopyran. This absorption band disappeared by irradiation of a 940-nm laser beam, since the upconversion powder emitted green light that caused bleaching of colored spirobenzopyran.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127249545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Paeglis, Inita Jokste, Kristine Bagucka, I. Lācis
Eye movement research of reading has been done on a battery of eye-tracking setups during last decades. We compared reading data of the same group of six students, their eyes were tracked by a video-based helmet-mounted system with the data sampling frequency of 50 Hz and a setup with a chin-rest at 240 Hz. We found that not only the number of fixations may decrease after reading practice, but so does also the mean duration of fixations. In spite of the short duration of saccades, their distributions and changes in them are similarly reported in the two experimental conditions. Lack of significant correlation in the HED data testifies to the result variability due to measurement technique. We conclude that the head-free setup is applicable in reading research but has insufficient precision to track changes in reading patterns.
{"title":"Eye movements during silent and oral reading with stabilized versus free head movement and different eye-trackers","authors":"R. Paeglis, Inita Jokste, Kristine Bagucka, I. Lācis","doi":"10.1117/12.815343","DOIUrl":"https://doi.org/10.1117/12.815343","url":null,"abstract":"Eye movement research of reading has been done on a battery of eye-tracking setups during last decades. We compared reading data of the same group of six students, their eyes were tracked by a video-based helmet-mounted system with the data sampling frequency of 50 Hz and a setup with a chin-rest at 240 Hz. We found that not only the number of fixations may decrease after reading practice, but so does also the mean duration of fixations. In spite of the short duration of saccades, their distributions and changes in them are similarly reported in the two experimental conditions. Lack of significant correlation in the HED data testifies to the result variability due to measurement technique. We conclude that the head-free setup is applicable in reading research but has insufficient precision to track changes in reading patterns.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129788541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work we present measurement and results of the deconvolution of the Hg 253.7 nm spectral line shapes, emitted from the mercury isotope high-frequency electrodeless discharge lamps, made at the Institute of Atomic Physics and Spectroscopy for the use in Zeeman Atomic Absorption Spectrometry. The emission line profiles of 254 nm Hg resonance line have been measured by means of a Zeeman scanning spectrometer at the mercury cold spot temperature value at 20 C. Then the deconvolution procedure or solving of this ill-posed inverse problem by means of the Tikhonov's regularization method [1] was performed to obtain the real spectral line shape.
{"title":"Deconvolution of the mercury 253.7 nm spectral line shape for the use in absorption spectroscopy","authors":"N. Zorina, G. Revalde, R. Disch","doi":"10.1117/12.815460","DOIUrl":"https://doi.org/10.1117/12.815460","url":null,"abstract":"In this work we present measurement and results of the deconvolution of the Hg 253.7 nm spectral line shapes, emitted from the mercury isotope high-frequency electrodeless discharge lamps, made at the Institute of Atomic Physics and Spectroscopy for the use in Zeeman Atomic Absorption Spectrometry. The emission line profiles of 254 nm Hg resonance line have been measured by means of a Zeeman scanning spectrometer at the mercury cold spot temperature value at 20 C. Then the deconvolution procedure or solving of this ill-posed inverse problem by means of the Tikhonov's regularization method [1] was performed to obtain the real spectral line shape.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126372391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Gurevich, S. Andreyev, V. Shapovalov, I. A. Kolesov, A. Belyaev
The experimental studies of the rough surface profile are described. These studies have been performed using acoustooptic tunable filters and optical components with strong chromatic aberration. The basic characteristic of the surface profilometer mock-up is longitudinal resolving power (by z-distance) which has to be defined according to the certain criterion. The proposed criterion is connected with the probability of missing of information unit which relates to the z-distance characterization of the device. The experimental circuit providing the surface profile measurements is described, and the experimental results are listed and discussed. The most interesting result is that defocusing is distinguished with 90% probability at electric frequency deviation of 200 kHz. The perspectives of the further improvement of information transmission by this device are discussed. It has been found that this improvement can be attained by means of the noise level decreasing to the level taking place for electric frequency of 94 MHz.
{"title":"Rough surfaces profile studies using acousto-optic tunable filter","authors":"B. Gurevich, S. Andreyev, V. Shapovalov, I. A. Kolesov, A. Belyaev","doi":"10.1117/12.815417","DOIUrl":"https://doi.org/10.1117/12.815417","url":null,"abstract":"The experimental studies of the rough surface profile are described. These studies have been performed using acoustooptic tunable filters and optical components with strong chromatic aberration. The basic characteristic of the surface profilometer mock-up is longitudinal resolving power (by z-distance) which has to be defined according to the certain criterion. The proposed criterion is connected with the probability of missing of information unit which relates to the z-distance characterization of the device. The experimental circuit providing the surface profile measurements is described, and the experimental results are listed and discussed. The most interesting result is that defocusing is distinguished with 90% probability at electric frequency deviation of 200 kHz. The perspectives of the further improvement of information transmission by this device are discussed. It has been found that this improvement can be attained by means of the noise level decreasing to the level taking place for electric frequency of 94 MHz.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"8 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133204763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We address theoretically adiabatic regime of charge transport for a model of two tunnel-coupled quantum dots connected in series. The energy levels of the two dots are harmonically modulated by an external potential with a constant phase shift between the two. Motivated by recent experiments with surface-acoustic-wave excitation, we consider two situations: (a) pure pumping in the absence of external voltage (also at finite temperature), and (b) adiabatic modulation of the current driven by large external bias. In both cases we derive results consistent with published experimental data. For the case (b) we explicitly derive the adiabatic limit of Tien-Gordon formula for photon-assisted tunneling and compare it to the outcome of simple conductance modulation. A tutorial for adiabatic pumping current calculations with the Green function formalism is included.
{"title":"Low-frequency excitation of double quantum dots","authors":"Vyacheslavs Kashcheyevs","doi":"10.1117/12.816583","DOIUrl":"https://doi.org/10.1117/12.816583","url":null,"abstract":"We address theoretically adiabatic regime of charge transport for a model of two tunnel-coupled quantum dots connected in series. The energy levels of the two dots are harmonically modulated by an external potential with a constant phase shift between the two. Motivated by recent experiments with surface-acoustic-wave excitation, we consider two situations: (a) pure pumping in the absence of external voltage (also at finite temperature), and (b) adiabatic modulation of the current driven by large external bias. In both cases we derive results consistent with published experimental data. For the case (b) we explicitly derive the adiabatic limit of Tien-Gordon formula for photon-assisted tunneling and compare it to the outcome of simple conductance modulation. A tutorial for adiabatic pumping current calculations with the Green function formalism is included.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122559653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Abromavičius, R. Buzelis, R. Drazdys, A. Melninkaitis, D. Mikšys, V. Sirutkaitis, A. Skrebutėnas
This investigation was aimed at optimization of optical properties, stability and radiation resistance of optical coatings deposited using the standard vacuum coating plant equipped with the ion source for ion assisted deposition. There are some reports showing that porous dielectric coatings are more resistant to intense laser radiation, however they have smaller environmental stability than denser coatings, which are more sensitive to laser radiation. The influence of important technological parameters (deposition rate, substrate temperature, energy of ions) on optical properties and radiation resistance of high reflection dielectric coatings based on Nb2O5/SiO2 and Ta2O5/SiO2 in VIS spectral region is presented.
{"title":"Improvement of optical properties and radiation resistance of optical coatings based on Nb2O5 and Ta2O5","authors":"G. Abromavičius, R. Buzelis, R. Drazdys, A. Melninkaitis, D. Mikšys, V. Sirutkaitis, A. Skrebutėnas","doi":"10.1117/12.726564","DOIUrl":"https://doi.org/10.1117/12.726564","url":null,"abstract":"This investigation was aimed at optimization of optical properties, stability and radiation resistance of optical coatings deposited using the standard vacuum coating plant equipped with the ion source for ion assisted deposition. There are some reports showing that porous dielectric coatings are more resistant to intense laser radiation, however they have smaller environmental stability than denser coatings, which are more sensitive to laser radiation. The influence of important technological parameters (deposition rate, substrate temperature, energy of ions) on optical properties and radiation resistance of high reflection dielectric coatings based on Nb2O5/SiO2 and Ta2O5/SiO2 in VIS spectral region is presented.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"1 3-4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120894380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new approach to control chemically the atomic structure and electronic properties of III-V compound semiconductors is developed. This approach is based on the modification of chemical properties of anionic adsorbates (such as HS- ions) prior to their adsorption on the surface. This is achieved through the solvation of the ions with different amphiprotic solvents (water, alcohols). Ab initio quantum-chemical calculations show that the reactivity of solvated HS- ions depends essentially on composition of the solvation shell: hydrated ions are slightly electrophilic, whereas ions solvated by alcohols are nucleophilic. Mechanism of interaction of such solvated ions with the semiconductor surface depends on the solvent solvating the ion. Experimentally it is found that on adsorption of HS- ions from different solvents the As-S bonds with solvent-dependent ionicity are formed on the surface. These surfaces possess different ionization energy and electronic properties though now traces of solvent molecules are found in XPS spectra.
{"title":"Chemical control over surface atomic structure and electronic properties of III-V semiconductors","authors":"M. Lebedev","doi":"10.1117/12.726476","DOIUrl":"https://doi.org/10.1117/12.726476","url":null,"abstract":"A new approach to control chemically the atomic structure and electronic properties of III-V compound semiconductors is developed. This approach is based on the modification of chemical properties of anionic adsorbates (such as HS- ions) prior to their adsorption on the surface. This is achieved through the solvation of the ions with different amphiprotic solvents (water, alcohols). Ab initio quantum-chemical calculations show that the reactivity of solvated HS- ions depends essentially on composition of the solvation shell: hydrated ions are slightly electrophilic, whereas ions solvated by alcohols are nucleophilic. Mechanism of interaction of such solvated ions with the semiconductor surface depends on the solvent solvating the ion. Experimentally it is found that on adsorption of HS- ions from different solvents the As-S bonds with solvent-dependent ionicity are formed on the surface. These surfaces possess different ionization energy and electronic properties though now traces of solvent molecules are found in XPS spectra.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131383649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Investigation and comparison of modeling and experimental results for the two-fiber reflection non contact displacement sensor are presented. The main aim of the research carried out here is to compare the two light emitting fiber constants obtained in the experiment and those obtained in the modeling process and set their values for the super light diode (SLD) and laser diode (LD) type sources. In the research paper the constants k and m (describing the distribution of the light emitting source beam intensity) values obtained, alongside with which a rather good match of the experiment and modeling results was obtained. In addition, the work presents some comparisons with the beam waist calculations in which the beam waist depends on the light wavelength &lgr;. The results of research have shown that it is possible to calculate the characteristics of fiber sensors precisely enough by means of modeling. The results obtained were used in the new compensation type two-fiber optopairs sensor.
{"title":"Investigation and comparison of modeling and experimental results for the fiber optopair reflection noncontact displacement sensor","authors":"V. Kleiza, J. Verkelis","doi":"10.1117/12.726461","DOIUrl":"https://doi.org/10.1117/12.726461","url":null,"abstract":"Investigation and comparison of modeling and experimental results for the two-fiber reflection non contact displacement sensor are presented. The main aim of the research carried out here is to compare the two light emitting fiber constants obtained in the experiment and those obtained in the modeling process and set their values for the super light diode (SLD) and laser diode (LD) type sources. In the research paper the constants k and m (describing the distribution of the light emitting source beam intensity) values obtained, alongside with which a rather good match of the experiment and modeling results was obtained. In addition, the work presents some comparisons with the beam waist calculations in which the beam waist depends on the light wavelength &lgr;. The results of research have shown that it is possible to calculate the characteristics of fiber sensors precisely enough by means of modeling. The results obtained were used in the new compensation type two-fiber optopairs sensor.","PeriodicalId":273853,"journal":{"name":"International Conference on Advanced Optical Materials and Devices","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131410525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：