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Ryo Yasuhara - One of the best experts on this subject based on the ideXlab platform.
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wavelength dependence of the Verdet Constant in synthetic quartz glass for deep ultraviolet light sources
Optical Materials Express, 2021Co-Authors: Yuki Tamaru, Hengjun Chen, Atsushi Fuchimukai, Hiyori Uehara, Taisuke Miura, Ryo YasuharaAbstract:Deep-ultraviolet (DUV) light sources are critical owing to their high photon energies and small diffraction limits, and synthetic quartz glass (SQ) is suitable for the Faraday rotators of DUV light. The Verdet Constant in SQ was evaluated within the wavelength range of 190–300 nm. In addition to a high Verdet Constant over the DUV region, this material exhibits a high transmittance without transitional absorption bands. The Verdet Constants were found to be 70.1 rad/(T·m) at 193 nm, which is the shortest observed wavelength for silica glass. SQ glass has excellent structural properties; thus, it is suitable as a DUV Faraday rotator for high-average-power optical isolators.
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Verdet Constant dispersion measurement of synthetic quartz in duv region
Laser Congress 2020 (ASSL LAC) (2020) paper JTh6A.19, 2020Co-Authors: Yuki Tamaru, Hengjun Chen, Atsushi Fuchimukai, Hiyori Uehara, Taisuke Miura, Ryo YasuharaAbstract:Verdet Constant dispersion in synthetic quartz was evaluated with DUV light sources. The Verdet Constant at 221 nm was determined to be 41.1 rad/Tm. The DUV optical isolator can realize with the moderate magnetic field.
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Verdet Constant of potassium terbium fluoride crystal as a function of wavelength and temperature
Optics Letters, 2020Co-Authors: David Vojna, Ryo Yasuhara, Ondřej Slezak, A Lucianetti, Hengjun Chen, Martin Duda, Wolfgang Schlichting, Kevin T Stevens, Tomas MocekAbstract:Potassium terbium fluoride KTb3F10 (KTF) crystal is a promising magneto-active material for creating multi-kilowatt average-power Faraday isolators operating at the visible and near-infrared wavelengths. Nevertheless, the key material’s parameter needed for the design of any Faraday isolator—the Verdet Constant, has not been comprehensively investigated yet. In this Letter, we report on measurement of the Verdet Constant of the KTF crystal for wavelengths between 600 and 1500 nm and for temperatures ranging from 15 to 295 K. A suitable model for the Verdet Constant as a function of wavelength and temperature has been developed and may be conveniently used for optimal design of KTF-based high-average-power Faraday isolators.
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temperature wavelength dependence of Verdet Constant of dy2o3 ceramics
Optical Materials Express, 2019Co-Authors: Ondřej Slezak, Ryo Yasuhara, A Lucianetti, David Vojna, Hiroaki Furuse, Tomas MocekAbstract:Temperature and wavelength dependence of the Verdet Constant of dysprosium sesquioxide (Dy2O3) transparent ceramics has been measured for the temperatures ranging from cryogenic 20K up to room temperature 297K and for the wavelength range starting from visible 0.6μm up to mid-infrared 2.3μm. Several absorption bands corresponding to the electronic transitions in Dy2O3 have been identified and removed from the data analysis due to high absorption of the matching wavelengths within these absorption bands. The Verdet Constant data has been fitted by the multi-transition model function covering the whole temperature and wavelength range. Such fitted function could be used for the detailed design of magneto-optical devices as well as for the analysis of physical properties of the material itself.
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near infrared wavelength dependence of Verdet Constant in tb 2 zr 2 o 7 transparent ceramics
European Quantum Electronics Conference, 2019Co-Authors: Ryo Yasuhara, Akio IkesueAbstract:Transparent ceramics are widely developing for optical windows, laser gain mediums, phosphors for the LED lighting, and magneto-optic (MO) applications. In particular, advantages from the glass material or the single crystal of MO ceramics are notable for the high-power lasers from the view point of the large size capability, good thermal properties, and superior magneto-optics properties. Now a day, ceramic technology can realize several kind of cubic oxide materials such as terbium gallium garnet (TGG) [1–4], terbium aluminium garnet (TAG) [5], and sesquioxides [6–8]. In addition of above materials, Tb 2 Zr 2 O 7 (TZO) transparent ceramics is a new candidate material for the high-power laser application. TZO has a relatively high concentration of Tb3+ ion, a cubic pyrochlore structure, and no intrinsic absorption in the near infrared (NIR) region. To evaluate the potential of this material for the high-power laser application, we have evaluated the near-infrared (NIR) wavelength dependence of Verdet Constant in TZO ceramics as the first time.
Shengming Zhou - One of the best experts on this subject based on the ideXlab platform.
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thermo optical properties of terbium aluminum garnet ceramics doped with silicon and titanium
Optics Letters, 2016Co-Authors: Aleksey Starobor, O Palashov, Shengming ZhouAbstract:The Verdet Constant and thermo-optical characteristics of a Si-doped and Ti-doped terbium aluminum garnet ceramics have been investigated. It is shown that the Verdet Constant of the samples is ∼40% higher than that of TGG ceramics at 1064 nm. The best samples of Si:TAG have magneto-optical figures of merit more than 1.5 times greater than those of TGG ceramics. Si:TAG is better than TGG ceramics as a medium for high-power Faraday isolators.
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high Verdet Constant of ti doped terbium aluminum garnet tag ceramics
Optical Materials Express, 2016Co-Authors: Hiroaki Furuse, Ryo Yasuhara, Keijiro Hiraga, Shengming ZhouAbstract:The temperature dependence of the Verdet Constant of a 0.8 at % Ti-doped terbium aluminum garnet (TAG) ceramics was investigated using lasers with wavelengths of 632.8 and 1064 nm. A high value of the Verdet Constant was obtained at 296 K – namely, 184 and 53 rad/Tm for 632.8 and 1064 nm, respectively. The Verdet Constant of the Ti:TAG ceramics at 1064 nm is about 1.5 times higher than that of the terbium gallium garnet (TGG) ceramics. The transmittance of this sample was about 75% at the wavelength of 1 μm. This material represents a possible candidate for next-generation devices that utilize the magneto-optic effect.
O Palashov - One of the best experts on this subject based on the ideXlab platform.
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magneto optical faraday effect in dysprosium oxide dy2o3 based ceramics obtained by vacuum sintering
Optics Letters, 2018Co-Authors: I L Snetkov, D A Permin, S S Balabanov, Alexey Yakovlev, O PalashovAbstract:The method of self-propagating high-temperature synthesis of submicron powders with subsequent vacuum sintering was used to produce a series of optical ceramics based on dysprosium oxide (DyxY0.95-xLa0.05)2O3, where x=0.7, 0.85, and 0.9. The influence of ceramics composition on optical transmission of the obtained samples was investigated. The studied materials had several transparency windows in the visible 500-730 nm, near-IR 1900-2300 nm, and mid-IR 3500-7500 nm ranges. The dependence of the Verdet Constant on wavelength in the 400-1940 nm range was measured for each ceramics composition, and analytical approximations were obtained. When Y and La dopants were used, the Verdet Constant depended linearly on the concentration of Dy3+ ions, and its value in the visible wavelength range was about twice that of the analogous value for a terbium gallium garnet crystal. The high transmission and relatively high Verdet Constant make the produced materials highly promising for fabricating Faraday devices for Tm3+ and Ho3+ lasers and for lasers emitting in the visible spectrum.
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study of the influence of tb sc al garnet crystal composition on Verdet Constant
Optical Materials, 2017Co-Authors: Igor Ivanov, I L Snetkov, O Palashov, D N Karimov, Vladimir V Kochurikhin, A V Masalov, V A Fedorov, D A Ksenofontov, Y K KabalovAbstract:Abstract The influence of the composition of Tb-Sc-Al garnet crystals (TSAG) on the value of Verdet Constant was investigated at the wavelengths of 400–1060 nm. It was found that this value increased both, with the decrease of Sc3+ ions content and with the decrease of lattice parameter. The value of Verdet Constant of TSAG crystals depend on lattice parameter value and increased from 0.168 to 0.198 min/(Oe cm) (at λ = 1064 nm) with the decrease of Sc3+ ions content from 1.76 to 1.3 f.u. The value of Verdet Constant for TSAG crystals with Sc3+ ions content of 1.3 f.u. can be described using one- and two-oscillator models with the same accuracy. The absorption at the wavelengths of 226 and 272 nm for the sample with a thickness of 13 μm was observed and wavelengths were used for calculations of Verdet Constant in accordance with the two-oscillator model.
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cryogenic temperature characteristics of Verdet Constant of terbium sesquioxide ceramics
Optical Materials, 2016Co-Authors: I L Snetkov, O PalashovAbstract:Abstract The dependence of the Verdet Constant on temperature in the (80–300 К) range for a promising magneto-active material terbium sesquioxide Tb 2 O 3 at the wavelengths of 405–1064 nm is considered. For each of the studied wavelengths, the Verdet Constant of the material cooled down to the liquid nitrogen temperature increased by more than a factor of 3.2 as compared to the room temperature value. Similarly to the other paramagnetics, the increase follows the law ∼1/T. Approximations for the temperature dependence of the Verdet Constant have been obtained and the value of 1/V·(dV/dT) has been estimated. This information is needed to determine the angle of rotation as well as the variation of the extinction ratio of a Faraday isolator with temperature and extremely important at creation a cryogenic Faraday devices.
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wavelength dependence of Verdet Constant of tb3 y2o3 ceramics
Applied Physics Letters, 2016Co-Authors: I L Snetkov, D A Permin, S S Balabanov, O PalashovAbstract:Samples of the magneto-active material—Tb3+:Y2O3ceramics with Tb3+ion concentrations of 10%, 20%, 30%, and 100% (Tb2O3)—were prepared and studied. The wavelength dependence of Verdet Constant in the 380 nm–1750 nm range was approximated for all investigated ceramic samples and was predicted for a pure Tb2O3material. Tb2O3ceramics demonstrates a more than three times higher Verdet Constant in comparison with terbium gallium garnet crystal or ceramics. The linear dependence of the Verdet Constant on Tb3+ion concentration in the Tb3+:Y2O3ceramics was demonstrated. The obtained data will be useful for fabricating magneto-optical elements of Faraday devices based on Tb3+:Y2O3 with arbitrary Tb3+ion concentration operating at room temperature in the wavelength range of 380 nm–1750 nm.
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thermo optical properties of terbium aluminum garnet ceramics doped with silicon and titanium
Optics Letters, 2016Co-Authors: Aleksey Starobor, O Palashov, Shengming ZhouAbstract:The Verdet Constant and thermo-optical characteristics of a Si-doped and Ti-doped terbium aluminum garnet ceramics have been investigated. It is shown that the Verdet Constant of the samples is ∼40% higher than that of TGG ceramics at 1064 nm. The best samples of Si:TAG have magneto-optical figures of merit more than 1.5 times greater than those of TGG ceramics. Si:TAG is better than TGG ceramics as a medium for high-power Faraday isolators.
Tomas Mocek - One of the best experts on this subject based on the ideXlab platform.
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Verdet Constant of potassium terbium fluoride crystal as a function of wavelength and temperature
Optics Letters, 2020Co-Authors: David Vojna, Ryo Yasuhara, Ondřej Slezak, A Lucianetti, Hengjun Chen, Martin Duda, Wolfgang Schlichting, Kevin T Stevens, Tomas MocekAbstract:Potassium terbium fluoride KTb3F10 (KTF) crystal is a promising magneto-active material for creating multi-kilowatt average-power Faraday isolators operating at the visible and near-infrared wavelengths. Nevertheless, the key material’s parameter needed for the design of any Faraday isolator—the Verdet Constant, has not been comprehensively investigated yet. In this Letter, we report on measurement of the Verdet Constant of the KTF crystal for wavelengths between 600 and 1500 nm and for temperatures ranging from 15 to 295 K. A suitable model for the Verdet Constant as a function of wavelength and temperature has been developed and may be conveniently used for optimal design of KTF-based high-average-power Faraday isolators.
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Verdet Constant of magneto active materials developed for high power faraday devices
Applied Sciences, 2019Co-Authors: David Vojna, Ondřej Slezak, A Lucianetti, Tomas MocekAbstract:We review the progress in the investigation of the Verdet Constant of new magneto-active materials for the Faraday-effect-based devices used in high-power laser systems. A practical methodology for advanced characterization of the Verdet Constant of these materials is presented, providing a useful tool for benchmarking the new materials. The experimental setup used for the characterization is a flexible and robust tool for evaluating the Faraday rotation angle induced in the magneto-active material, from which the Verdet Constant is calculated based on the knowledge of the magnetic field and the material sample parameters. A general model for describing the measured Verdet Constant data as a function of wavelength and temperature is given. In the final part of this review, we present a brief overview of several magneto-active materials, which have been to-date reported as promising candidates for utilization in the Faraday devices. This overview covers room-temperature investigations of the Verdet Constant of several materials, which could be used for the ultraviolet, visible, near-infrared and mid-infrared wavelengths.
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temperature wavelength dependence of Verdet Constant of dy2o3 ceramics
Optical Materials Express, 2019Co-Authors: Ondřej Slezak, Ryo Yasuhara, A Lucianetti, David Vojna, Hiroaki Furuse, Tomas MocekAbstract:Temperature and wavelength dependence of the Verdet Constant of dysprosium sesquioxide (Dy2O3) transparent ceramics has been measured for the temperatures ranging from cryogenic 20K up to room temperature 297K and for the wavelength range starting from visible 0.6μm up to mid-infrared 2.3μm. Several absorption bands corresponding to the electronic transitions in Dy2O3 have been identified and removed from the data analysis due to high absorption of the matching wavelengths within these absorption bands. The Verdet Constant data has been fitted by the multi-transition model function covering the whole temperature and wavelength range. Such fitted function could be used for the detailed design of magneto-optical devices as well as for the analysis of physical properties of the material itself.
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characterization of the Verdet Constant of dy 2 o 3 ceramics in the two micron spectral range
European Quantum Electronics Conference, 2019Co-Authors: David Vojna, Ryo Yasuhara, A Lucianetti, Tomas Mocek, Hiroaki Furuse, Ondrej Slezak, Miroslav CechAbstract:High-power solid-state mid-IR lasers are being actively developed, as they possess the key properties for a vast number of technological applications [1] (e. g. lidar, gas sensing, or pump sources optical parametric oscillators) and are in a high demand for basic research as well [2]. These potentialities have recently led to intensive investigations of new mid-IR laser gain media [3,4] and other optical elements. One of the key components under investigation is an optical isolator (OI), a magneto-optical device enabling safe operation of a laser by preventing harmful back-reflections into the laser cavity. The development of high-power OIs is particularly challenging due to the severe thermal effects which arise because of the relatively high absorption of the currently available magneto-optical elements. Therefore, a lot of scientific effort is being put into the research of novel magneto-optical materials with the desired properties: high Verdet Constant, low absorption and excellent thermal properties. All of these properties enable a reduction of the heat generated in the magneto-optical element.
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Verdet Constant dispersion of cef 3 in the visible and near infrared spectral range
Optical Engineering, 2017Co-Authors: David Vojna, Ryo Yasuhara, A Lucianetti, Ondrej Slezak, Jiri Mužik, Tomas MocekAbstract:The Verdet Constant dispersion of CeF3 crystal was measured in the spectral range from 0.45 to 1.95 μm. To the best of our knowledge, CeF3 crystal was investigated for the first time as a potential material candidate for near-infrared Faraday rotators (FRs). The experimental results obtained for Verdet Constant dispersion were compared to other magneto-optical materials with the conclusion that CeF3 crystal possesses up to 60% higher Verdet Constant in the near-infrared spectral region 1.1 to 1.5 μm compared to widely used terbium gallium garnet crystal. Furthermore, the presented experimental setup is capable of high precision measurement of Verdet Constant dispersion in a broad spectral range, with measurement error not exceeding 5%, therefore, representing a powerful tool for FRs development.
Hiroaki Furuse - One of the best experts on this subject based on the ideXlab platform.
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temperature wavelength dependence of Verdet Constant of dy2o3 ceramics
Optical Materials Express, 2019Co-Authors: Ondřej Slezak, Ryo Yasuhara, A Lucianetti, David Vojna, Hiroaki Furuse, Tomas MocekAbstract:Temperature and wavelength dependence of the Verdet Constant of dysprosium sesquioxide (Dy2O3) transparent ceramics has been measured for the temperatures ranging from cryogenic 20K up to room temperature 297K and for the wavelength range starting from visible 0.6μm up to mid-infrared 2.3μm. Several absorption bands corresponding to the electronic transitions in Dy2O3 have been identified and removed from the data analysis due to high absorption of the matching wavelengths within these absorption bands. The Verdet Constant data has been fitted by the multi-transition model function covering the whole temperature and wavelength range. Such fitted function could be used for the detailed design of magneto-optical devices as well as for the analysis of physical properties of the material itself.
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characterization of the Verdet Constant of dy 2 o 3 ceramics in the two micron spectral range
European Quantum Electronics Conference, 2019Co-Authors: David Vojna, Ryo Yasuhara, A Lucianetti, Tomas Mocek, Hiroaki Furuse, Ondrej Slezak, Miroslav CechAbstract:High-power solid-state mid-IR lasers are being actively developed, as they possess the key properties for a vast number of technological applications [1] (e. g. lidar, gas sensing, or pump sources optical parametric oscillators) and are in a high demand for basic research as well [2]. These potentialities have recently led to intensive investigations of new mid-IR laser gain media [3,4] and other optical elements. One of the key components under investigation is an optical isolator (OI), a magneto-optical device enabling safe operation of a laser by preventing harmful back-reflections into the laser cavity. The development of high-power OIs is particularly challenging due to the severe thermal effects which arise because of the relatively high absorption of the currently available magneto-optical elements. Therefore, a lot of scientific effort is being put into the research of novel magneto-optical materials with the desired properties: high Verdet Constant, low absorption and excellent thermal properties. All of these properties enable a reduction of the heat generated in the magneto-optical element.
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magneto optical characteristics of holmium oxide ho 2 o 3 ceramics
Optical Materials Express, 2017Co-Authors: Hiroaki Furuse, Ryo YasuharaAbstract:Transparent Ho2O3 ceramics are fabricated and their magneto-optical characteristics are reported for the first time, to the best of our knowledge. The value of the Verdet Constant was measured in the 560–1064 nm wavelength range, and the value at 1064 nm is 46.3 rad/Tm. This corresponds to the Verdet Constant for terbium aluminum garnet (TAG), which is ~1.3 times higher than that of terbium gallium garnet (TGG). The in-line transmittance at 1 μm wavelength is only ~60%, but the optical properties can be further improved by optimizing sintering conditions. This is a new potential magneto-optic material that can be applicable for high-average-power lasers.
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high Verdet Constant of ti doped terbium aluminum garnet tag ceramics
Optical Materials Express, 2016Co-Authors: Hiroaki Furuse, Ryo Yasuhara, Keijiro Hiraga, Shengming ZhouAbstract:The temperature dependence of the Verdet Constant of a 0.8 at % Ti-doped terbium aluminum garnet (TAG) ceramics was investigated using lasers with wavelengths of 632.8 and 1064 nm. A high value of the Verdet Constant was obtained at 296 K – namely, 184 and 53 rad/Tm for 632.8 and 1064 nm, respectively. The Verdet Constant of the Ti:TAG ceramics at 1064 nm is about 1.5 times higher than that of the terbium gallium garnet (TGG) ceramics. The transmittance of this sample was about 75% at the wavelength of 1 μm. This material represents a possible candidate for next-generation devices that utilize the magneto-optic effect.
