Pub Date : 2018-01-01DOI: 10.4172/2469-410X.1000180
N. Liu, S. Wu
A scheme to generate optical arbitrary waveform based on a Dual Parallel Mach-Zehnder modulator (DPMZM) and an optical filter is proposed. One of the child MZMs (MZM-1) of the DPMZM is driven by the Ratio Frequency (RF) and DC bias voltage (Vbias-1), at the same time, the other child MZM (MZM-2) is driven by the RF multiplier and the DC bias voltage (Vbias-2). By adjusting the size of the RF driving voltages and the DC bias voltages, we can get a stable optical frequency comb with high side-comb suppression ratio (SCSR). Then optical frequency comb (OFC) matches with the tunable optical filter by adjusting the spectral line position and spacing, the waveforms of Gaussian, Trapezoid, square wave, sine, half-wave cosine and sinc-shaped pulse with a tunable repetition rate are generated.
{"title":"Generation of Arbitrary Waveform Based on Optical Frequency Comb Using a Dual Parallel Mach-Zehnder Modulator and an Optical Filter","authors":"N. Liu, S. Wu","doi":"10.4172/2469-410X.1000180","DOIUrl":"https://doi.org/10.4172/2469-410X.1000180","url":null,"abstract":"A scheme to generate optical arbitrary waveform based on a Dual Parallel Mach-Zehnder modulator (DPMZM) and an optical filter is proposed. One of the child MZMs (MZM-1) of the DPMZM is driven by the Ratio Frequency (RF) and DC bias voltage (Vbias-1), at the same time, the other child MZM (MZM-2) is driven by the RF multiplier and the DC bias voltage (Vbias-2). By adjusting the size of the RF driving voltages and the DC bias voltages, we can get a stable optical frequency comb with high side-comb suppression ratio (SCSR). Then optical frequency comb (OFC) matches with the tunable optical filter by adjusting the spectral line position and spacing, the waveforms of Gaussian, Trapezoid, square wave, sine, half-wave cosine and sinc-shaped pulse with a tunable repetition rate are generated.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82744432","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}
Pub Date : 2018-01-01DOI: 10.4172/2469-410X.1000175
B. Roy, A. Tsui, O. Oni, B. Vlahovic
In a contactless photo conductance measurement system the radio-frequency (RF) probe transmission (ΔV/ V0) should be proportional to the product of laser-induced carrier concentration and carrier mobility (IΣμ) through a sensitivity factor (A). We use 532 nm laser (pump)-millimeter wave (mmw-probe) system whose concentrations (I) are calculated by considering single-surface reflection of the laser beam and mobility (Σμ) derived from a model. In order to ascertain A we use five c-Si (100) samples having resistivity in the range 15-130 Ω-cm. For relating (ΔV/V0) with IΣμ to find A, we take their ratio and quantify A once using a quadratic-fit functional form of the ratio of sample resistivity to air resistivity (ρ/ρ0), and another time using product of free-space impedance and sample thickness (ρ/Z0t). A is ascertained for (ΔV/V0)-laser fluence linear region while fluence is in range 0-1.7 μJ/cm2 and probe frequency is fixed at 140 GHz. Value of A is further fine-tuned by multiplying with 0.85 (to linearize the ratio with the non-dimensional function) and finally obtain sensitivity A=0.291. Standard error in mmw photo conductance (obtained using calculated A) between the two approaches diminish with laser attenuation roughly at a rate ± 0.53 × 10-5 S, per decimal neutral density filter size.
{"title":"Inter-Relation between Laser Induced Photoconductance and Millimeter Wave Absorption Using C-Si Intrinsic Resistivity","authors":"B. Roy, A. Tsui, O. Oni, B. Vlahovic","doi":"10.4172/2469-410X.1000175","DOIUrl":"https://doi.org/10.4172/2469-410X.1000175","url":null,"abstract":"In a contactless photo conductance measurement system the radio-frequency (RF) probe transmission (ΔV/ V0) should be proportional to the product of laser-induced carrier concentration and carrier mobility (IΣμ) through a sensitivity factor (A). We use 532 nm laser (pump)-millimeter wave (mmw-probe) system whose concentrations (I) are calculated by considering single-surface reflection of the laser beam and mobility (Σμ) derived from a model. In order to ascertain A we use five c-Si (100) samples having resistivity in the range 15-130 Ω-cm. For relating (ΔV/V0) with IΣμ to find A, we take their ratio and quantify A once using a quadratic-fit functional form of the ratio of sample resistivity to air resistivity (ρ/ρ0), and another time using product of free-space impedance and sample thickness (ρ/Z0t). A is ascertained for (ΔV/V0)-laser fluence linear region while fluence is in range 0-1.7 μJ/cm2 and probe frequency is fixed at 140 GHz. Value of A is further fine-tuned by multiplying with 0.85 (to linearize the ratio with the non-dimensional function) and finally obtain sensitivity A=0.291. Standard error in mmw photo conductance (obtained using calculated A) between the two approaches diminish with laser attenuation roughly at a rate ± 0.53 × 10-5 S, per decimal neutral density filter size.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88452326","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}
Pub Date : 2017-12-20DOI: 10.4172/2469-410X.1000170
M. Abouricha, A. Boulezhar, S. Amrane, N. Azami
We present in this paper the special structure of photonic crystal fiber (PCF), the temperature-dependent Yb3+ photonic crystal fiber lasers model with stimulated Brillouin scattering (SBS) is presented by solving the steady-state rate equations with the (SBS) in the linear cavity. The numerical results show that the pump power, laser power and stokes powers propagating along axial positions are obtained by using the finite difference method and shooting method. The comparison results of the photonic crystal fiber laser model without temperature factor, the output powers and the SBS threshold powers in different pump schemes are obtained in the simulation paragraph. The numerical results show that the SBS threshold power in the two-end pump scheme is more noticeable than other pumps schemes.
{"title":"Stimulated Brillouin Scattering in High-Power Photonic Crystal Fiber Lasers in Different Pump Schemes","authors":"M. Abouricha, A. Boulezhar, S. Amrane, N. Azami","doi":"10.4172/2469-410X.1000170","DOIUrl":"https://doi.org/10.4172/2469-410X.1000170","url":null,"abstract":"We present in this paper the special structure of photonic crystal fiber (PCF), the temperature-dependent Yb3+ photonic crystal fiber lasers model with stimulated Brillouin scattering (SBS) is presented by solving the steady-state rate equations with the (SBS) in the linear cavity. The numerical results show that the pump power, laser power and stokes powers propagating along axial positions are obtained by using the finite difference method and shooting method. The comparison results of the photonic crystal fiber laser model without temperature factor, the output powers and the SBS threshold powers in different pump schemes are obtained in the simulation paragraph. The numerical results show that the SBS threshold power in the two-end pump scheme is more noticeable than other pumps schemes.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88434739","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}
Pub Date : 2017-11-10DOI: 10.4172/2469-410X-C1-015
S. Budnik
U (UV) photonic devices such as laser diodes (LDs) and light-emitting diodes (LEDs) have drawn great interest in many applications including lighting, optical storage, and purification. From a theoretical viewpoint, III-nitride (III-N) semiconductors can be good candidates for UV photonic application because of its band gap which may cover a wide wavelength range of ultraviolet (UV) to visible red. The (Al,Ga,In)N multiple quantum wells (MQWs) are extensively used as active region for deep UV wavelengths. These structures are characterized by the existence of both spontaneous and piezoelectric polarization arising from the lack of lattice-matched substrate. The polarization-induced internal electric field causes charge separation which leads to reduction in TE-polarized spontaneous emission radiative recombination rate (Rsp) and TE-polarized optical gain (GTE). One of the challenges for high efficiency UV lasers is the need to reduce this internal electric field. We present here a comprehensive analysis of structure based on III-N quaternary QWs as an alternative for high efficiency deep-UV lasers using the 8x8 wurtzite k.p Hamiltonian matrix to calculate the energies band structures and the wave functions by taking into account the valence band anisotropy mixing, the interband interaction and the spontaneous and piezoelectric polarization. Simulation of lasers performance are realized using matlab genetic algorithm. Our proposed design is optimized by adjusting the (Al,In) content and thickness of the sublayers of staggered AluInvGa1-u-vN/AlxInyGa1-x-yNdelta-AlxGa1-xN QWs surrounded by quaternary AlInGaN for peak emission wavelengths at 229 nm. since TE-polarized optical gain peak intensity larger than such achieved by conventional AlInN-delta-GaN-based QWs.
{"title":"Theory of unified matter","authors":"S. Budnik","doi":"10.4172/2469-410X-C1-015","DOIUrl":"https://doi.org/10.4172/2469-410X-C1-015","url":null,"abstract":"U (UV) photonic devices such as laser diodes (LDs) and light-emitting diodes (LEDs) have drawn great interest in many applications including lighting, optical storage, and purification. From a theoretical viewpoint, III-nitride (III-N) semiconductors can be good candidates for UV photonic application because of its band gap which may cover a wide wavelength range of ultraviolet (UV) to visible red. The (Al,Ga,In)N multiple quantum wells (MQWs) are extensively used as active region for deep UV wavelengths. These structures are characterized by the existence of both spontaneous and piezoelectric polarization arising from the lack of lattice-matched substrate. The polarization-induced internal electric field causes charge separation which leads to reduction in TE-polarized spontaneous emission radiative recombination rate (Rsp) and TE-polarized optical gain (GTE). One of the challenges for high efficiency UV lasers is the need to reduce this internal electric field. We present here a comprehensive analysis of structure based on III-N quaternary QWs as an alternative for high efficiency deep-UV lasers using the 8x8 wurtzite k.p Hamiltonian matrix to calculate the energies band structures and the wave functions by taking into account the valence band anisotropy mixing, the interband interaction and the spontaneous and piezoelectric polarization. Simulation of lasers performance are realized using matlab genetic algorithm. Our proposed design is optimized by adjusting the (Al,In) content and thickness of the sublayers of staggered AluInvGa1-u-vN/AlxInyGa1-x-yNdelta-AlxGa1-xN QWs surrounded by quaternary AlInGaN for peak emission wavelengths at 229 nm. since TE-polarized optical gain peak intensity larger than such achieved by conventional AlInN-delta-GaN-based QWs.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77891112","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}
Pub Date : 2017-09-30DOI: 10.4172/2469-410X.1000164
Apollonov Vv
The issue of the light speed invariance, experimentally studied by Aleksandrov et al. seems to be very important. It is shown that Aleksandrov et al. did not take into account a number of factors that lead to a significant difference from the reference data when calculating the speed of light by the method proposed. An accurate analysis of the experiment aimed at measuring the speed of synchrotron radiation allows us to state that it can be equal to 2c. A new experiment is needed in which the synchronization signal from an induction loop introducing an uncertainty is replaced by a signal from the second light detector installed near the radiation point.
{"title":"Experiments directly demonstrating that the speed of light is independent of the velocity of the source: An experimental fact or a misconception","authors":"Apollonov Vv","doi":"10.4172/2469-410X.1000164","DOIUrl":"https://doi.org/10.4172/2469-410X.1000164","url":null,"abstract":"The issue of the light speed invariance, experimentally studied by Aleksandrov et al. seems to be very important. It is shown that Aleksandrov et al. did not take into account a number of factors that lead to a significant difference from the reference data when calculating the speed of light by the method proposed. An accurate analysis of the experiment aimed at measuring the speed of synchrotron radiation allows us to state that it can be equal to 2c. A new experiment is needed in which the synchronization signal from an induction loop introducing an uncertainty is replaced by a signal from the second light detector installed near the radiation point.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74478671","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}
Pub Date : 2017-09-01DOI: 10.4172/2469-410X.1000E112
R. Miglani
{"title":"Free Space Optical Communication: The Last Mile Solution to High Speed Communication Networks","authors":"R. Miglani","doi":"10.4172/2469-410X.1000E112","DOIUrl":"https://doi.org/10.4172/2469-410X.1000E112","url":null,"abstract":"","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78578045","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}
Pub Date : 2017-06-30DOI: 10.4172/2469-410X.1000156
S. Pokutnyi
In framework of dipole approximation it is shown, that the oscillator strengths of transitions as well as the dipole moments for transitions for one-particle electron Coulomb states emerging above the spherical surface quantum dot of metal assume giant values considerably (by two orders of magnitude) exceeding the typical values of the corresponding quantities for dielectrics. It has been established that the giant values of the light absorption cross section in the nanosystems under investigation make it possible to use such nanosystems as strongly absorbing nanomaterials in a wide range of infrared waves with a wavelength that can be varied in a wide range depending in the type of contacting materials.
{"title":"Strongly Optical Absorbing Nanostructures Containing Metal QuantumDots: Theory","authors":"S. Pokutnyi","doi":"10.4172/2469-410X.1000156","DOIUrl":"https://doi.org/10.4172/2469-410X.1000156","url":null,"abstract":"In framework of dipole approximation it is shown, that the oscillator strengths of transitions as well as the dipole moments for transitions for one-particle electron Coulomb states emerging above the spherical surface quantum dot of metal assume giant values considerably (by two orders of magnitude) exceeding the typical values of the corresponding quantities for dielectrics. It has been established that the giant values of the light absorption cross section in the nanosystems under investigation make it possible to use such nanosystems as strongly absorbing nanomaterials in a wide range of infrared waves with a wavelength that can be varied in a wide range depending in the type of contacting materials.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79523521","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}
Pub Date : 2017-06-30DOI: 10.4172/2469-410X.1000162
Musayev Ma, Hesenov Qt, Hashimova Nn, Ceferova An
Optothermodynamic method of diagnosis of absorption coefficient of waves in inhomogeneous absorbing liquids has been developed temperature influence on wave’s absorption coefficient has been determined. Optothermodynamic method allows establishing relation between optic and thermophysical properties of liquid. Developed method is based on the application of energy conservation on the interaction of laser beams with inhomogeneous absorbing liquids.
{"title":"Optothermodynamic Method of Diagnosis of Absorption Coefficient in theLiquids","authors":"Musayev Ma, Hesenov Qt, Hashimova Nn, Ceferova An","doi":"10.4172/2469-410X.1000162","DOIUrl":"https://doi.org/10.4172/2469-410X.1000162","url":null,"abstract":"Optothermodynamic method of diagnosis of absorption coefficient of waves in inhomogeneous absorbing liquids has been developed temperature influence on wave’s absorption coefficient has been determined. Optothermodynamic method allows establishing relation between optic and thermophysical properties of liquid. Developed method is based on the application of energy conservation on the interaction of laser beams with inhomogeneous absorbing liquids.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75125766","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}
Pub Date : 2017-06-30DOI: 10.4172/2469-410X.1000159
B. Marina, B. Narkiza, K. Borodina, S. Sorokina
In the laboratory of physics and general technical disciplines of the Ugra State University, an optoelectronic measuring system based on a high-speed Video Sprint video camera is used for research. The calibration of ECO has revealed a number of nonlinear effects. In the paper, a method is described that allows eliminating the afterglow of the screen of the image converter. The method is based on revealing the law of attenuation of the afterglow of a phosphor. As a result of the application, data loss is reduced, the signal-to-noise ratio is increased.
{"title":"Method of Elimination of the Residual Lumination of the LuminescentCovering of Screen","authors":"B. Marina, B. Narkiza, K. Borodina, S. Sorokina","doi":"10.4172/2469-410X.1000159","DOIUrl":"https://doi.org/10.4172/2469-410X.1000159","url":null,"abstract":"In the laboratory of physics and general technical disciplines of the Ugra State University, an optoelectronic measuring system based on a high-speed Video Sprint video camera is used for research. The calibration of ECO has revealed a number of nonlinear effects. In the paper, a method is described that allows eliminating the afterglow of the screen of the image converter. The method is based on revealing the law of attenuation of the afterglow of a phosphor. As a result of the application, data loss is reduced, the signal-to-noise ratio is increased.","PeriodicalId":92245,"journal":{"name":"Journal of lasers, optics & photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87618486","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}
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