The wavelength demultiplexing is a particularly important function in integrated optics and can be realized using photonic crystals. The aim is to extract accurately the wavelengths in a data flux. In this work, we investigate a new topologies of wavelength demultiplexing based on two-dimensional photonic crystals constituted of dielectric rods spread in a square network. The studied demultiplexer is based on optical filters with optimized parameters in order to extract four different wavelengths in the vicinity of frequencies corresponding to communication windows. It was found that the crosstalk between the structure channels of the demultiplexer are in the range of –19.19 and –44.1 dB and the channel spacing is equal to 0.96 nm. The simulation results presented in this paper are performed and analyzed using the FDTD method.
{"title":"Four channel optical demultiplexer based on L2 photonic crystal microcavity","authors":"Merzoug Ammari, A. Benmerkhi, M. Bouchemat","doi":"10.37190/oa220411","DOIUrl":"https://doi.org/10.37190/oa220411","url":null,"abstract":"The wavelength demultiplexing is a particularly important function in integrated optics and can be realized using photonic crystals. The aim is to extract accurately the wavelengths in a data flux. In this work, we investigate a new topologies of wavelength demultiplexing based on two-dimensional photonic crystals constituted of dielectric rods spread in a square network. The studied demultiplexer is based on optical filters with optimized parameters in order to extract four different wavelengths in the vicinity of frequencies corresponding to communication windows. It was found that the crosstalk between the structure channels of the demultiplexer are in the range of –19.19 and –44.1 dB and the channel spacing is equal to 0.96 nm. The simulation results presented in this paper are performed and analyzed using the FDTD method.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70017489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, we proposed a highly sensitive design of a plasmonic sensor which is formed by embedding a periodic array of nanoblocks in L-shaped cavity formed by the metal–insulator–metal waveguide. The nanoblocks are placed in the strong electric field confinement region to further enhance its strength by confining it to a small area. To validate the study, the spectral characteristics of the proposed sensor design is compared to the spectral characteristics of a standard design having the same geometric parameters excluding nanoblocks in the cavity. The study shows that the incorporation of 5 nanoblocks of length 25 nm in the cavity can provide best performance indicators in the form of sensitivity, figure of merit and Q-factor. The sensitivity, figure of merit and Q-factor of the proposed sensor design is 1065 nm/RIU, 251.17 and 343.4 which is significantly higher than the standard L-shape resonator design. The sensor design can be developed with a single fabrication step. Due to the ease of fabrication and the highly responsive nature of the design, it can be used in biomedical applications.
{"title":"Nanoblocks embedded in L-shaped nanocavity of a plasmonic sensor for best sensor performance","authors":"M. A. Butt, N. Kazanskiy","doi":"10.37190/OA210109","DOIUrl":"https://doi.org/10.37190/OA210109","url":null,"abstract":"In this work, we proposed a highly sensitive design of a plasmonic sensor which is formed by embedding a periodic array of nanoblocks in L-shaped cavity formed by the metal–insulator–metal waveguide. The nanoblocks are placed in the strong electric field confinement region to further enhance its strength by confining it to a small area. To validate the study, the spectral characteristics of the proposed sensor design is compared to the spectral characteristics of a standard design having the same geometric parameters excluding nanoblocks in the cavity. The study shows that the incorporation of 5 nanoblocks of length 25 nm in the cavity can provide best performance indicators in the form of sensitivity, figure of merit and Q-factor. The sensitivity, figure of merit and Q-factor of the proposed sensor design is 1065 nm/RIU, 251.17 and 343.4 which is significantly higher than the standard L-shape resonator design. The sensor design can be developed with a single fabrication step. Due to the ease of fabrication and the highly responsive nature of the design, it can be used in biomedical applications.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70010123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A multi-wavelength bidirectional Brillouin-erbium fiber ring laser with switchable Brillouin frequency spacing (BFS) is proposed and experimentally demonstrated. In the presented Brillouin-erbium ring laser, including an optical amplifier and a highly nonlinear fiber, and without any optical isolator, due to Rayleigh scattering, stimulated Brillouin scattering, and cascaded four-wave mixing initiated successively by the Brillouin pump (BP) light, the odd- and even-order Stokes lines are generated and circulate in the opposite direction in the ring cavity. The BP light and Stokes-induced Rayleigh backscattering light also simultaneously circulate in the ring cavity. Only by adjusting BP power, the gain competition between Brillouin based Stokes and cavity modes’ oscillation can be controlled, the laser output can be conveniently switched between single BFS and odd- or even-order double BFS. In addition, under the certain BP power conditions, the proposed multi-wavelength Brillouin-erbium fiber laser also can realize switchable odd- or even-order Stokes generation and Stokes generation with single BFS, with an increasing wavelength number in turn, only by simply adjusting pump power of the erbium-doped fiber amplifier. Stability and wavelength tunability of the proposed multi-wavelength bidirectional Brillouin-erbium fiber ring laser are also investigated, respectively.
{"title":"Investigation of a tunable and switchable multi-wavelength bidirectional Brillouin-erbium fiber ring laser","authors":"F. Wang, R.Y. Yuan","doi":"10.37190/oa210306","DOIUrl":"https://doi.org/10.37190/oa210306","url":null,"abstract":"A multi-wavelength bidirectional Brillouin-erbium fiber ring laser with switchable Brillouin frequency spacing (BFS) is proposed and experimentally demonstrated. In the presented Brillouin-erbium ring laser, including an optical amplifier and a highly nonlinear fiber, and without any optical isolator, due to Rayleigh scattering, stimulated Brillouin scattering, and cascaded four-wave mixing initiated successively by the Brillouin pump (BP) light, the odd- and even-order Stokes lines are generated and circulate in the opposite direction in the ring cavity. The BP light and Stokes-induced Rayleigh backscattering light also simultaneously circulate in the ring cavity. Only by adjusting BP power, the gain competition between Brillouin based Stokes and cavity modes’ oscillation can be controlled, the laser output can be conveniently switched between single BFS and odd- or even-order double BFS. In addition, under the certain BP power conditions, the proposed multi-wavelength Brillouin-erbium fiber laser also can realize switchable odd- or even-order Stokes generation and Stokes generation with single BFS, with an increasing wavelength number in turn, only by simply adjusting pump power of the erbium-doped fiber amplifier. Stability and wavelength tunability of the proposed multi-wavelength bidirectional Brillouin-erbium fiber ring laser are also investigated, respectively.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70012951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hong Li, Haoyue Zhang, Yanming Song, Fanyong Meng, Lianqing Zhu
A novel technology for the simultaneous and independent measurement of dual parameters is proposed and experimented. By using a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing conditions, the sensor structure is designed such that the reflective single-peak spectrum splits into a twin-peak spectrum, which makes the FBG spectrum form a natural spectral peak splitting bias. A measurement limitation exists in the FBG sensor packaging at room temperature, which can be solved by the high-temperature cured packaging method. To verify the validity of the theory and methodology, the experimental system is used. In the range from –1000 to +1000 με and from 35 to 75°C, the Bragg wavelength change is relative linear to the strain and temperature. The temperature and strain variations can be independently and simultaneously measured using the split peak, and the deviations of the FBG sensor are ±1°C and ±5 με, respectively. This single FBG sensor can realize dual-parameter measurement, which is valuable for narrow-space health monitoring.
{"title":"Dual-parameter sensing characteristics of a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing","authors":"Hong Li, Haoyue Zhang, Yanming Song, Fanyong Meng, Lianqing Zhu","doi":"10.37190/oa210307","DOIUrl":"https://doi.org/10.37190/oa210307","url":null,"abstract":"A novel technology for the simultaneous and independent measurement of dual parameters is proposed and experimented. By using a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing conditions, the sensor structure is designed such that the reflective single-peak spectrum splits into a twin-peak spectrum, which makes the FBG spectrum form a natural spectral peak splitting bias. A measurement limitation exists in the FBG sensor packaging at room temperature, which can be solved by the high-temperature cured packaging method. To verify the validity of the theory and methodology, the experimental system is used. In the range from –1000 to +1000 με and from 35 to 75°C, the Bragg wavelength change is relative linear to the strain and temperature. The temperature and strain variations can be independently and simultaneously measured using the split peak, and the deviations of the FBG sensor are ±1°C and ±5 με, respectively. This single FBG sensor can realize dual-parameter measurement, which is valuable for narrow-space health monitoring.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70012984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We report a numerical investigation of how the dispersion slope affects the soliton spectral tunneling (SST) in a photonic crystal fiber with three zero dispersion wavelengths. It is discovered that a larger dispersion slope makes group-velocity mismatch between the initial soliton and the transferred wave thereby suppressing the SST effect, while a proper decrease of the dispersion slope enhances the SST effect to widen a supercontinuum range. Besides, we find a soliton-like leaking dispersion wave, which can sustain information and energy for a short time within a particular spectral range.
{"title":"Influence of dispersion slope on soliton spectral tunneling in photonic crystal fiber","authors":"Yunxia Yang, Hua Yang, Xiongfeng Tong, Saili Zhao, Shuyuan Chen","doi":"10.37190/oa210309","DOIUrl":"https://doi.org/10.37190/oa210309","url":null,"abstract":"We report a numerical investigation of how the dispersion slope affects the soliton spectral tunneling (SST) in a photonic crystal fiber with three zero dispersion wavelengths. It is discovered that a larger dispersion slope makes group-velocity mismatch between the initial soliton and the transferred wave thereby suppressing the SST effect, while a proper decrease of the dispersion slope enhances the SST effect to widen a supercontinuum range. Besides, we find a soliton-like leaking dispersion wave, which can sustain information and energy for a short time within a particular spectral range.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70013488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. B. Khairulazdan, R. Mohamed, D. Berhanuddin, P. Menon
Kretschmann-based surface plasmon resonance (K-SPR) is suitable for biomolecular sensing which provides label-free and quick detection results with real-time analysis. In this work, we have investigated the effect of graphene oxide (GO) with titanium dioxide (TiO2) thin films that are placed in hybrid above metal layers such as gold (Au), silver (Ag) and copper (Cu) with the presence of chromium (Cr) as an adhesive layer. The thickness of the Au, Ag and Cu metal thin films were optimized to 40, 30 and 30 nm, respectively, with a fixed thickness of GO of 2 nm and TiO2 of 1.9 nm. The sensing was evaluated for SPR excitation at three different visible wavelengths of 633, 670 and 785 nm. The performance of sensing was analyzed based on the reflectance intensity and full-width at half-maximum (FWHM) of the spectrum using the finite-difference time-domain (FDTD) method. The sensitivity was calculated for analyte sensing in dielectric mediums of air versus water. The sensitivity increment percentage (%ΔS) was determined when comparing analyte detection using Cr/metal and Cr/metal/GO/TiO2 sensor structures. The highest sensitivity of 94.51 deg/RIU was achieved for Cr/Cu/GO/TiO2 K-SPR sensor at 633 nm wavelength.
{"title":"Characterisation of nano-thin film GO/TiO2 layers for Kretschmann-based surface plasmon resonance visible sensing using FDTD method","authors":"N. B. Khairulazdan, R. Mohamed, D. Berhanuddin, P. Menon","doi":"10.37190/oa210409","DOIUrl":"https://doi.org/10.37190/oa210409","url":null,"abstract":"Kretschmann-based surface plasmon resonance (K-SPR) is suitable for biomolecular sensing which provides label-free and quick detection results with real-time analysis. In this work, we have investigated the effect of graphene oxide (GO) with titanium dioxide (TiO2) thin films that are placed in hybrid above metal layers such as gold (Au), silver (Ag) and copper (Cu) with the presence of chromium (Cr) as an adhesive layer. The thickness of the Au, Ag and Cu metal thin films were optimized to 40, 30 and 30 nm, respectively, with a fixed thickness of GO of 2 nm and TiO2 of 1.9 nm. The sensing was evaluated for SPR excitation at three different visible wavelengths of 633, 670 and 785 nm. The performance of sensing was analyzed based on the reflectance intensity and full-width at half-maximum (FWHM) of the spectrum using the finite-difference time-domain (FDTD) method. The sensitivity was calculated for analyte sensing in dielectric mediums of air versus water. The sensitivity increment percentage (%ΔS) was determined when comparing analyte detection using Cr/metal and Cr/metal/GO/TiO2 sensor structures. The highest sensitivity of 94.51 deg/RIU was achieved for Cr/Cu/GO/TiO2 K-SPR sensor at 633 nm wavelength.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70014235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katarzyna Perz-Juszczyszyn, M. Feltzke, Katarzyna Dubas, W. C. Maples, B. Kolodziejczak, H. Buczkowska
Background: Measurements of phoria at near are important elements of the optometric assessment of binocular vision. It is important to know if different methods of measuring a phoria are interchangeable. This study was designed to compare phoria measures using in-phoropter (von Graefe) and in free space methods (Howell card). Methods: The study was conducted with 70 pre-presbyopic subjects, aged 23–35 years. Both near the von Graefe and near Howell card horizontal dissociated phorias along and with gradient +1.00 D and –1.00 D phorias were measured for each technique. Results: The mean values of the near dissociated phoria, for both test conditions (von Graefe and Howell card) showed a slight deviation in the two measures with von Graefe measures being generally more exophoric. The mean value of the phoropter phoria was 1.97 ∆ base-in and in free space, the value was 0.9 ∆ base-in. The phoropter phoria with the +1.00 D gradient was 5.24 ∆ base-in, and in free space, 2.73 ∆ base-in. Measurements of the phorometric phoria with a gradient of –1.00 D gave a mean of 0.42 ∆ base-out and 0.94 ∆ base-out in free space. The near phoria measures were significantly different for the basic near measure (p = 0.01) and for the +1.00 D gradient (p = 0.000002) but not for the –1.00 D measure (p = 0.36). Conclusion: The results of the differences in the near horizontal phoria in free space and in- phoropter were significantly different for the basic measure and for the +1.00 D gradient. The findings between the two methods of testing should therefore not be treated as equivalent or convertible. Each test method should have separate means and ranges established.
{"title":"Comparison of near horizontal heterophoria tests in free space and with phoropter","authors":"Katarzyna Perz-Juszczyszyn, M. Feltzke, Katarzyna Dubas, W. C. Maples, B. Kolodziejczak, H. Buczkowska","doi":"10.37190/oa210204","DOIUrl":"https://doi.org/10.37190/oa210204","url":null,"abstract":"Background: Measurements of phoria at near are important elements of the optometric assessment of binocular vision. It is important to know if different methods of measuring a phoria are interchangeable. This study was designed to compare phoria measures using in-phoropter (von Graefe) and in free space methods (Howell card). Methods: The study was conducted with 70 pre-presbyopic subjects, aged 23–35 years. Both near the von Graefe and near Howell card horizontal dissociated phorias along and with gradient +1.00 D and –1.00 D phorias were measured for each technique. Results: The mean values of the near dissociated phoria, for both test conditions (von Graefe and Howell card) showed a slight deviation in the two measures with von Graefe measures being generally more exophoric. The mean value of the phoropter phoria was 1.97 ∆ base-in and in free space, the value was 0.9 ∆ base-in. The phoropter phoria with the +1.00 D gradient was 5.24 ∆ base-in, and in free space, 2.73 ∆ base-in. Measurements of the phorometric phoria with a gradient of –1.00 D gave a mean of 0.42 ∆ base-out and 0.94 ∆ base-out in free space. The near phoria measures were significantly different for the basic near measure (p = 0.01) and for the +1.00 D gradient (p = 0.000002) but not for the –1.00 D measure (p = 0.36). Conclusion: The results of the differences in the near horizontal phoria in free space and in- phoropter were significantly different for the basic measure and for the +1.00 D gradient. The findings between the two methods of testing should therefore not be treated as equivalent or convertible. Each test method should have separate means and ranges established.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70011657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yushuang Wang, Xuanxuan Ji, Ziyang Chen, Jixiong Pu
We develop a Q-switched degenerate laser, delivering a partially coherent light pulse of duration about 16 ns. The spatial coherence of the output laser pulse can be varied by tuning the spatial filter inside the laser resonator, and the oscillating transverse mode structure can be determined by measuring the degree of coherence of the output laser pulse. It is shown that the larger is the diameter of the spatial filter, the more are the oscillating transverse modes, and the lower is the degree of coherence. Based on coherent-mode representation for the partially coherent source, we can estimate the transverse mode contribution to the output partially coherent laser. The experimental results on suppressing speckle demonstrate that the generated partially coherent light possesses the characteristics of rapid reduction of spatial coherence, making it an ideal source for high-speed imaging and ranging applications.
{"title":"Q-switched partially coherent lasers with controllable spatial coherence","authors":"Yushuang Wang, Xuanxuan Ji, Ziyang Chen, Jixiong Pu","doi":"10.37190/oa210208","DOIUrl":"https://doi.org/10.37190/oa210208","url":null,"abstract":"We develop a Q-switched degenerate laser, delivering a partially coherent light pulse of duration about 16 ns. The spatial coherence of the output laser pulse can be varied by tuning the spatial filter inside the laser resonator, and the oscillating transverse mode structure can be determined by measuring the degree of coherence of the output laser pulse. It is shown that the larger is the diameter of the spatial filter, the more are the oscillating transverse modes, and the lower is the degree of coherence. Based on coherent-mode representation for the partially coherent source, we can estimate the transverse mode contribution to the output partially coherent laser. The experimental results on suppressing speckle demonstrate that the generated partially coherent light possesses the characteristics of rapid reduction of spatial coherence, making it an ideal source for high-speed imaging and ranging applications.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70012111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Todorovic, P. Spalevic, S. Panic, Bojana Milosavljević, Milan Gligorijevic
In order to provide a novel analytically traceable free space optics (FSO) channel model for describing turbulence based irradiance fluctuations, following basic scintillation theory principles, we have derived closed-form expression for probability density function (PDF) of a new statistical Gamma–Chi-square model. Further, capitalizing on provided model, error performances of FSO system over on–off keying (OOK) transmission scheme both in the presence of atmospheric turbulence and misalignment fading (pointing error) is investigated. For both cases, the average bit error rate (ABER) at the receiving side of the system is determined in an analytically closed form. The results are graphically presented in order to analyze the impact of different levels of turbulence, as well as other relevant parameters, on the quality of the received signal in the OOK modulated FSO system.
{"title":"FSO system performance analysis based on novel Gamma–Chi-square irradiance PDF model","authors":"J. Todorovic, P. Spalevic, S. Panic, Bojana Milosavljević, Milan Gligorijevic","doi":"10.37190/oa210303","DOIUrl":"https://doi.org/10.37190/oa210303","url":null,"abstract":"In order to provide a novel analytically traceable free space optics (FSO) channel model for describing turbulence based irradiance fluctuations, following basic scintillation theory principles, we have derived closed-form expression for probability density function (PDF) of a new statistical Gamma–Chi-square model. Further, capitalizing on provided model, error performances of FSO system over on–off keying (OOK) transmission scheme both in the presence of atmospheric turbulence and misalignment fading (pointing error) is investigated. For both cases, the average bit error rate (ABER) at the receiving side of the system is determined in an analytically closed form. The results are graphically presented in order to analyze the impact of different levels of turbulence, as well as other relevant parameters, on the quality of the received signal in the OOK modulated FSO system.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70012410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A stable composition (against crystallization) of germanate glass doped with Yb3+ for mid-infrared laser applications is presented. Broad emission spectrum of Yb3+ was obtained for the fabricated glass. Laser operation was demonstrated in 13 mm long waveguide written in the glass using a femtosecond laser operating at 524 nm center wavelength sending 250 fs ultrashort pulses. The resulting CW laser operated at 1.04 μm in the fundamental mode of the waveguide. The propagation loss through the waveguide was 0.6 dB/cm at 1550 nm for 45 μm diameter of the modified structure. The mode analysis of the developed waveguide structure is also presented in COMSOL Multiphysics to study the electric field distribution through different modes of propagation in the waveguide and the confinement loss associated to them.
{"title":"Broadband fluorescence emission and laser demonstration in large mode waveguide structure in Yb3+ doped germanate glass","authors":"M. Khalid","doi":"10.37190/OA210106","DOIUrl":"https://doi.org/10.37190/OA210106","url":null,"abstract":"A stable composition (against crystallization) of germanate glass doped with Yb3+ for mid-infrared laser applications is presented. Broad emission spectrum of Yb3+ was obtained for the fabricated glass. Laser operation was demonstrated in 13 mm long waveguide written in the glass using a femtosecond laser operating at 524 nm center wavelength sending 250 fs ultrashort pulses. The resulting CW laser operated at 1.04 μm in the fundamental mode of the waveguide. The propagation loss through the waveguide was 0.6 dB/cm at 1550 nm for 45 μm diameter of the modified structure. The mode analysis of the developed waveguide structure is also presented in COMSOL Multiphysics to study the electric field distribution through different modes of propagation in the waveguide and the confinement loss associated to them.","PeriodicalId":19589,"journal":{"name":"Optica Applicata","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70009484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}