The Experts below are selected from a list of 17787 Experts worldwide ranked by ideXlab platform
C H A Huan - One of the best experts on this subject based on the ideXlab platform.
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trends in bonding configuration at sic iii v Semiconductor interfaces
Applied Physics Letters, 2001Co-Authors: Jincheng Zheng, Huiqiong Wang, C H A HuanAbstract:The structural and electronic properties of interfaces between β-SiC and III–V Semiconductors are studied by first-principles calculations. Favorable bonding configurations are found to form between Si–V and C–III (model A) for BN, AlN, AlP, AlAs, GaN, GaP, GaAs, InN, InP, InAs, and InSb, and Si–III and C–V (model B) for BP, BAs, BSb, AlSb, and GaSb. The relationship between the formation energy difference and lattice constant difference, as well as the charge distribution, for these two models is found. The origin of bonding configurations can be explained in terms of the ionicity of III–V Semiconductors, electrostatic effect, charge distribution, and band-structure component.
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Trends in bonding configuration at SiC/III-V Semiconductor interfaces
Applied Physics Letters, 2001Co-Authors: Jincheng Zheng, Huiqiong Wang, C H A HuanAbstract:The structural and electronic properties of interfaces between β-SiC and III–V Semiconductors are studied by first-principles calculations. Favorable bonding configurations are found to form between Si–V and C–III (model A) for BN, AlN, AlP, AlAs, GaN, GaP, GaAs, InN, InP, InAs, and InSb, and Si–III and C–V (model B) for BP, BAs, BSb, AlSb, and GaSb. The relationship between the formation energy difference and lattice constant difference, as well as the charge distribution, for these two models is found. The origin of bonding configurations can be explained in terms of the ionicity of III–V Semiconductors, electrostatic effect, charge distribution, and band-structure component.
John E. Bowers - One of the best experts on this subject based on the ideXlab platform.
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Heterogeneous Silicon/III–V Semiconductor Optical Amplifiers
IEEE Journal of Selected Topics in Quantum Electronics, 2016Co-Authors: Michael L. Davenport, Sandra Skendžić, Nicolas Volet, Jared C. Hulme, Martijn J. R. Heck, John E. BowersAbstract:We report high output power and high-gain Semiconductor optical amplifiers integrated on a heterogeneous silicon/III-V photonics platform. The devices produce 25 dB of unsaturated gain for the highest gain design, and 14 dBm of saturated output power for the highest output power design. The amplifier structure is also suitable for lasers, and can be readily integrated with a multitude of silicon photonic circuit components. These devices are useful for a wide range of photonic integrated circuits. We show a design method for optimizing the amplifier for the desired characteristics. The amplifier incorporates a low loss and low reflection transition between the heterogeneous active region and a silicon waveguide, and we report transition loss below 1 dB across the entire measurement range and parasitic reflection coefficient from the transition below 1 · 10-3.
Isabelle Sagnes - One of the best experts on this subject based on the ideXlab platform.
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Generation of new coherent light states using III-V Semiconductor laser technology: VORTEX, continuum, dual frequency for THz and integration
2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO Europe-EQEC), 2017Co-Authors: Arnaud Garnache, Mohamed S. Seghilani, Mikhael Myara, M. Sellahi, R. Paquet, B. Chomet, S. Blin, L. Legratiet, G. Beaudoin, Isabelle SagnesAbstract:Since years, III-V Semiconductor based external-cavity VCSEL (VECSEL) concept [1] is pointed out as a technology of choice for beyond-state-of-the-art laser light sources, demonstrating wavelength flexibility, high power, high spatial, temporal and polarization coherence, CW or fs ultra-short pulsed operation, compactness and functionalities. The targeted coherent state is typically a common circular low divergence fundamental gaussian TEM00 mode, linearly polarized state, single frequency state or modelocked comb. Such high-Q laser cavity exhibits a class-A dynamics with low intensity noise at shot noise level in MHz-GHz RF range, as well as a quantum limit optical frequency noise at the Hz level. Integration and packaging of such high performances sources is in progress (by Coherent, Innoptics [2], Fraunhofer ILT...). In this work, we take advantage of diode-pumped VECSEL based on III-V nanotechnologies integrating flat-photonics (quantum-well gain, Bragg mirror, metasurface, metallic mask), and fundamental physical features (axial symmetry of laser design, orthogonality of cavity modes, high finesse cavity, homogeneous gain, optical gain structure anisotropy, spatial hole burning...) for the generation of non-conventional coherent states, thanks to the insertion of new intracavity functions: beam carrying Orbital-Angular-Momentum, dual-frequency optical source for THz, coherent modeless light source.
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Coherent and Tunable THz Emission Driven by an Integrated III–V Semiconductor Laser
IEEE Journal of Selected Topics in Quantum Electronics, 2017Co-Authors: Stéphane Blin, Mohamed Sellahi, Grégoire Beaudoin, Mikhael Myara, Isabelle Sagnes, Romain Paquet, Baptiste Chomet, Luc Le Gratiet, Guillaume Ducournau, Philipp LatzelAbstract:We demonstrate coherent and tunable THz emission by excitation of a unitraveling-carrier photodiode by a dual-frequency III-V Semiconductor laser emitting up to 80 mW of optical power around 1 μm. The laser is an optically-pumped vertical-external-cavity surface-emitting laser that operates simultaneously on two transverse Laguerre-Gauss modes. Modes frequency difference is driven by thermal effects, band-filling effects and/or phase masks, allowing THz emission from 50 GHz to few THz. To reach THz emission from a pigtailed photodiode, we detail quantitatively how orthogonal transverse modes can be coupled within a single-mode fiber, leading to more than 20% beat efficiency. Coherent THz emission spectrum is presented with a linewidth of about 150 kHz for 3-ms acquisition time, and an output power limited by the photodiode (typically 1 μW at 300 GHz). Frequency noise is measured for the optical transverse modes along with the THz signal. The latter presents a frequency noise that is about 20-dB lower than the optical ones, thus proving that the dual-frequency concept allows frequency noise reduction by correlating part of the technical noise of the two modes.
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Vortex Laser based on III-V Semiconductor metasurface: direct generation of coherent Laguerre-Gauss modes carrying controlled orbital angular momentum
Scientific Reports, 2016Co-Authors: Mohamed S. Seghilani, Mohamed Sellahi, Luc Legratiet, Grégoire Beaudoin, Mikhael Myara, Philippe Lalanne, Isabelle Sagnes, Arnaud GarnacheAbstract:The generation of a coherent state, supporting a large photon number, with controlled orbital-angular-momentum L = ħl (of charge l per photon) presents both fundamental and technological challenges: we demonstrate a surface-emitting laser, based on III-V Semiconductor technology with an integrated metasurface, generating vortex-like coherent state in the Laguerre-Gauss basis. We use a first order phase perturbation to lift orbital degeneracy of wavefunctions, by introducing a weak anisotropy called here " orbital birefringence " , based on a dielectric metasurface. The azimuthal symmetry breakdown and non-linear laser dynamics create " orbital gain dichroism " allowing selecting vortex handedness. This coherent photonic device was characterized and studied, experimentally and theoretically. It exhibits a low divergence (50 dB vortex purity), and single frequency operation in a stable low noise regime (0.1% rms). Such high performance laser opens the path to widespread new photonic applications. Optical vortex beams have known a growing interest since the first realization that they carry an Orbital Angular Momentum (OAM) L 1 (Fig. 1). The development of such beams has led to many advanced applications such as optical handling of microscopic particles 2 , atoms manipulation 3,4 , sub-diffraction limit microscopy 5 , laser mate-rial processing 6,7 , and quantum information processing and telecommunication 8–12 . Together with photon energy ħω and linear momentum ħk, the angular momentum = + J L S is one of the most important characteristics of light 1 . For paraxial fields in free space, the eigenmodes of J operator are circularly-polarized helically phased beams, where polarization helicity σ = ± 1 (or 0 for linear state in anisotropic media) specifies the value of Spin Angular Momentum (SAM) per photon S = σħ, whereas the vortex integer topological charge l = 0, ± 1, ± 2, ... yields the OAM per photon L = ħl. The sign of l gives the direction of rotation of the wave-front. A striking difference between L and S momenta is the range of allowed values, while σ is bounded between − 1 and + 1, l can take much higher values. Vortex helical wave-fronts vary azimuthally with θ in a corkscrew-like manner along direction of propagation z, with a Poynting vector that follows a spiral trajec-tory around the axis. The wave-function reads as ∝ e i(θl−kz)
Arnaud Garnache - One of the best experts on this subject based on the ideXlab platform.
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Generation of new coherent light states using III-V Semiconductor laser technology: VORTEX, continuum, dual frequency for THz and integration
2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO Europe-EQEC), 2017Co-Authors: Arnaud Garnache, Mohamed S. Seghilani, Mikhael Myara, M. Sellahi, R. Paquet, B. Chomet, S. Blin, L. Legratiet, G. Beaudoin, Isabelle SagnesAbstract:Since years, III-V Semiconductor based external-cavity VCSEL (VECSEL) concept [1] is pointed out as a technology of choice for beyond-state-of-the-art laser light sources, demonstrating wavelength flexibility, high power, high spatial, temporal and polarization coherence, CW or fs ultra-short pulsed operation, compactness and functionalities. The targeted coherent state is typically a common circular low divergence fundamental gaussian TEM00 mode, linearly polarized state, single frequency state or modelocked comb. Such high-Q laser cavity exhibits a class-A dynamics with low intensity noise at shot noise level in MHz-GHz RF range, as well as a quantum limit optical frequency noise at the Hz level. Integration and packaging of such high performances sources is in progress (by Coherent, Innoptics [2], Fraunhofer ILT...). In this work, we take advantage of diode-pumped VECSEL based on III-V nanotechnologies integrating flat-photonics (quantum-well gain, Bragg mirror, metasurface, metallic mask), and fundamental physical features (axial symmetry of laser design, orthogonality of cavity modes, high finesse cavity, homogeneous gain, optical gain structure anisotropy, spatial hole burning...) for the generation of non-conventional coherent states, thanks to the insertion of new intracavity functions: beam carrying Orbital-Angular-Momentum, dual-frequency optical source for THz, coherent modeless light source.
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Vortex Laser based on III-V Semiconductor metasurface: direct generation of coherent Laguerre-Gauss modes carrying controlled orbital angular momentum
Scientific Reports, 2016Co-Authors: Mohamed S. Seghilani, Mohamed Sellahi, Luc Legratiet, Grégoire Beaudoin, Mikhael Myara, Philippe Lalanne, Isabelle Sagnes, Arnaud GarnacheAbstract:The generation of a coherent state, supporting a large photon number, with controlled orbital-angular-momentum L = ħl (of charge l per photon) presents both fundamental and technological challenges: we demonstrate a surface-emitting laser, based on III-V Semiconductor technology with an integrated metasurface, generating vortex-like coherent state in the Laguerre-Gauss basis. We use a first order phase perturbation to lift orbital degeneracy of wavefunctions, by introducing a weak anisotropy called here " orbital birefringence " , based on a dielectric metasurface. The azimuthal symmetry breakdown and non-linear laser dynamics create " orbital gain dichroism " allowing selecting vortex handedness. This coherent photonic device was characterized and studied, experimentally and theoretically. It exhibits a low divergence (50 dB vortex purity), and single frequency operation in a stable low noise regime (0.1% rms). Such high performance laser opens the path to widespread new photonic applications. Optical vortex beams have known a growing interest since the first realization that they carry an Orbital Angular Momentum (OAM) L 1 (Fig. 1). The development of such beams has led to many advanced applications such as optical handling of microscopic particles 2 , atoms manipulation 3,4 , sub-diffraction limit microscopy 5 , laser mate-rial processing 6,7 , and quantum information processing and telecommunication 8–12 . Together with photon energy ħω and linear momentum ħk, the angular momentum = + J L S is one of the most important characteristics of light 1 . For paraxial fields in free space, the eigenmodes of J operator are circularly-polarized helically phased beams, where polarization helicity σ = ± 1 (or 0 for linear state in anisotropic media) specifies the value of Spin Angular Momentum (SAM) per photon S = σħ, whereas the vortex integer topological charge l = 0, ± 1, ± 2, ... yields the OAM per photon L = ħl. The sign of l gives the direction of rotation of the wave-front. A striking difference between L and S momenta is the range of allowed values, while σ is bounded between − 1 and + 1, l can take much higher values. Vortex helical wave-fronts vary azimuthally with θ in a corkscrew-like manner along direction of propagation z, with a Poynting vector that follows a spiral trajec-tory around the axis. The wave-function reads as ∝ e i(θl−kz)
Mikhael Myara - One of the best experts on this subject based on the ideXlab platform.
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Generation of new coherent light states using III-V Semiconductor laser technology: VORTEX, continuum, dual frequency for THz and integration
2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO Europe-EQEC), 2017Co-Authors: Arnaud Garnache, Mohamed S. Seghilani, Mikhael Myara, M. Sellahi, R. Paquet, B. Chomet, S. Blin, L. Legratiet, G. Beaudoin, Isabelle SagnesAbstract:Since years, III-V Semiconductor based external-cavity VCSEL (VECSEL) concept [1] is pointed out as a technology of choice for beyond-state-of-the-art laser light sources, demonstrating wavelength flexibility, high power, high spatial, temporal and polarization coherence, CW or fs ultra-short pulsed operation, compactness and functionalities. The targeted coherent state is typically a common circular low divergence fundamental gaussian TEM00 mode, linearly polarized state, single frequency state or modelocked comb. Such high-Q laser cavity exhibits a class-A dynamics with low intensity noise at shot noise level in MHz-GHz RF range, as well as a quantum limit optical frequency noise at the Hz level. Integration and packaging of such high performances sources is in progress (by Coherent, Innoptics [2], Fraunhofer ILT...). In this work, we take advantage of diode-pumped VECSEL based on III-V nanotechnologies integrating flat-photonics (quantum-well gain, Bragg mirror, metasurface, metallic mask), and fundamental physical features (axial symmetry of laser design, orthogonality of cavity modes, high finesse cavity, homogeneous gain, optical gain structure anisotropy, spatial hole burning...) for the generation of non-conventional coherent states, thanks to the insertion of new intracavity functions: beam carrying Orbital-Angular-Momentum, dual-frequency optical source for THz, coherent modeless light source.
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Coherent and Tunable THz Emission Driven by an Integrated III–V Semiconductor Laser
IEEE Journal of Selected Topics in Quantum Electronics, 2017Co-Authors: Stéphane Blin, Mohamed Sellahi, Grégoire Beaudoin, Mikhael Myara, Isabelle Sagnes, Romain Paquet, Baptiste Chomet, Luc Le Gratiet, Guillaume Ducournau, Philipp LatzelAbstract:We demonstrate coherent and tunable THz emission by excitation of a unitraveling-carrier photodiode by a dual-frequency III-V Semiconductor laser emitting up to 80 mW of optical power around 1 μm. The laser is an optically-pumped vertical-external-cavity surface-emitting laser that operates simultaneously on two transverse Laguerre-Gauss modes. Modes frequency difference is driven by thermal effects, band-filling effects and/or phase masks, allowing THz emission from 50 GHz to few THz. To reach THz emission from a pigtailed photodiode, we detail quantitatively how orthogonal transverse modes can be coupled within a single-mode fiber, leading to more than 20% beat efficiency. Coherent THz emission spectrum is presented with a linewidth of about 150 kHz for 3-ms acquisition time, and an output power limited by the photodiode (typically 1 μW at 300 GHz). Frequency noise is measured for the optical transverse modes along with the THz signal. The latter presents a frequency noise that is about 20-dB lower than the optical ones, thus proving that the dual-frequency concept allows frequency noise reduction by correlating part of the technical noise of the two modes.
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Vortex Laser based on III-V Semiconductor metasurface: direct generation of coherent Laguerre-Gauss modes carrying controlled orbital angular momentum
Scientific Reports, 2016Co-Authors: Mohamed S. Seghilani, Mohamed Sellahi, Luc Legratiet, Grégoire Beaudoin, Mikhael Myara, Philippe Lalanne, Isabelle Sagnes, Arnaud GarnacheAbstract:The generation of a coherent state, supporting a large photon number, with controlled orbital-angular-momentum L = ħl (of charge l per photon) presents both fundamental and technological challenges: we demonstrate a surface-emitting laser, based on III-V Semiconductor technology with an integrated metasurface, generating vortex-like coherent state in the Laguerre-Gauss basis. We use a first order phase perturbation to lift orbital degeneracy of wavefunctions, by introducing a weak anisotropy called here " orbital birefringence " , based on a dielectric metasurface. The azimuthal symmetry breakdown and non-linear laser dynamics create " orbital gain dichroism " allowing selecting vortex handedness. This coherent photonic device was characterized and studied, experimentally and theoretically. It exhibits a low divergence (50 dB vortex purity), and single frequency operation in a stable low noise regime (0.1% rms). Such high performance laser opens the path to widespread new photonic applications. Optical vortex beams have known a growing interest since the first realization that they carry an Orbital Angular Momentum (OAM) L 1 (Fig. 1). The development of such beams has led to many advanced applications such as optical handling of microscopic particles 2 , atoms manipulation 3,4 , sub-diffraction limit microscopy 5 , laser mate-rial processing 6,7 , and quantum information processing and telecommunication 8–12 . Together with photon energy ħω and linear momentum ħk, the angular momentum = + J L S is one of the most important characteristics of light 1 . For paraxial fields in free space, the eigenmodes of J operator are circularly-polarized helically phased beams, where polarization helicity σ = ± 1 (or 0 for linear state in anisotropic media) specifies the value of Spin Angular Momentum (SAM) per photon S = σħ, whereas the vortex integer topological charge l = 0, ± 1, ± 2, ... yields the OAM per photon L = ħl. The sign of l gives the direction of rotation of the wave-front. A striking difference between L and S momenta is the range of allowed values, while σ is bounded between − 1 and + 1, l can take much higher values. Vortex helical wave-fronts vary azimuthally with θ in a corkscrew-like manner along direction of propagation z, with a Poynting vector that follows a spiral trajec-tory around the axis. The wave-function reads as ∝ e i(θl−kz)
