A channel-drop filter has been designed based on the two-dimensional triangular-lattice hole photonic-crystal structure, which consists of two line defects and two point defects, by a two-dimensional finite-difference...A channel-drop filter has been designed based on the two-dimensional triangular-lattice hole photonic-crystal structure, which consists of two line defects and two point defects, by a two-dimensional finite-difference time-domain simulation.展开更多
Light scattering by a two-dimensional photonic-crystal slab(PCS)can result in marked interference effects associated with Fano resonances.Such devices offer appealing alternatives to distributed Bragg reflectors and f...Light scattering by a two-dimensional photonic-crystal slab(PCS)can result in marked interference effects associated with Fano resonances.Such devices offer appealing alternatives to distributed Bragg reflectors and filters for various applications,such as optical wavelength and polarization filters,reflectors,semiconductor lasers,photodetectors,bio-sensors and non-linear optical components.Suspended PCS also have natural applications in the field of optomechanics,where the mechanical modes of a suspended slab interact via radiation pressure with the optical field of a high-finesse cavity.The reflectivity and transmission properties of a defect-free suspended PCS around normal incidence can be used to couple out-of-plane mechanical modes to an optical field by integrating it in a free-space cavity.Here we demonstrate the successful implementation of a PCS reflector on a high-tensile stress Si_(3)N_(4) nanomembrane.We illustrate the physical process underlying the high reflectivity by measuring the photonic-crystal band diagram.Moreover,we introduce a clear theoretical description of the membrane scattering properties in the presence of optical losses.By embedding the PCS inside a high-finesse cavity,we fully characterize its optical properties.The spectrally,angular-and polarization-resolved measurements demonstrate the wide tunability of the membrane’s reflectivity,from nearly 0 to 99.9470±0.0025%,and show that material absorption is not the main source of optical loss.Moreover,the cavity storage time demonstrated in this work exceeds the mechanical period of low-order mechanical drum modes.This so-called resolved-sideband condition is a prerequisite to achieve quantum control of the mechanical resonator with light.展开更多
In this paper, we presented switching dynamic investigations on an InP photonic-crystal (PhC) nanocavity structure using homodyne pump-probe measurements. The measurements were compared with simulations based on tem...In this paper, we presented switching dynamic investigations on an InP photonic-crystal (PhC) nanocavity structure using homodyne pump-probe measurements. The measurements were compared with simulations based on temporal nonlinear coupled mode theory and carrier rate equations for the dynamics of the carrier density governing the cavity properties. The results provide insight into the nonlinear optical processes that govern the dynamics of nanocavities.展开更多
The filtering mechanism of a free output coupler mode-locked laser based on large-mode-area photonic-crystal fibre is analysed. A filtering-soliton mode-locked laser with 495 fs pulse width and 21 nJ pulse energy is a...The filtering mechanism of a free output coupler mode-locked laser based on large-mode-area photonic-crystal fibre is analysed. A filtering-soliton mode-locked laser with 495 fs pulse width and 21 nJ pulse energy is achieved. Another novel cavity configuration is established to eliminate the filtering effect. Pulses, each 457 fs in width and 16.5 nJ in energy, are obtained in a soliton-like regime. Pulses, each 387 fs in width and 15.8 nJ in energy, are also generated in a stretched pulse regime and could be dechirped to 119 fs externally to the cavity.展开更多
By using the complex finite element method (FEM) under perfectly matched layer (PML) boundary conditions, dispersion properties of microstructured optical fibres (MOFs) with elliptical air holes are analysed by ...By using the complex finite element method (FEM) under perfectly matched layer (PML) boundary conditions, dispersion properties of microstructured optical fibres (MOFs) with elliptical air holes are analysed by changing the pitch and sizes of air holes belonging to the inner three rings. Meanwhile, the confinement loss of the fundamental mode is engineered to achieve the single-polarization single-mode transmission. Based on this analysis, a novel design of MOFs for properties of the single-polarization single-mode and the nearly zero ultraflattened dispersion between lpskm^-1 nm^-1 in the wavelength range of 1.2-1.6μm is presented for the first time.展开更多
Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre desig...Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre designs that allow for very large mode areas at high average powers with diffraction-limited beam quality are of enormous interest.Ytterbium-doped,rod-type,large-pitch fibres(LPF)enable extreme fibre dimensions,i.e.,effective single-mode fibres with mode sizes exceeding 100 times the wavelength of the guided radiation,by exploiting the novel concept of delocalisation of higher-order transverse modes.The non-resonant nature of the operating principle makes LPF suitable for high power extraction.This design allows for an unparalleled level of performance in pulsed fibre lasers.展开更多
基金This work has been supported in part by the Korea ScienceEngineering Foundation through the UFON-ERC Program, by Ministry of Information+1 种基金 Communication through the CHOAN-ITRC Program by Ministry of Education through the BK-21-IT Program.
文摘A channel-drop filter has been designed based on the two-dimensional triangular-lattice hole photonic-crystal structure, which consists of two line defects and two point defects, by a two-dimensional finite-difference time-domain simulation.
基金funded by the Agence Nationale de la Recherche programs‘ANR-2011-BS04-029 MiNOToRe’and‘ANR-14-CE26-0002 QuNaT’the Marie Curie Initial Training Network‘cQOM’+2 种基金the DIM nano-K Ile-de-France program‘NanoMecAtom’supported by the Marie Sklodowska-Curie Individual Fellowship programsupported by a fellowship'Research in Paris'from the city of Paris.
文摘Light scattering by a two-dimensional photonic-crystal slab(PCS)can result in marked interference effects associated with Fano resonances.Such devices offer appealing alternatives to distributed Bragg reflectors and filters for various applications,such as optical wavelength and polarization filters,reflectors,semiconductor lasers,photodetectors,bio-sensors and non-linear optical components.Suspended PCS also have natural applications in the field of optomechanics,where the mechanical modes of a suspended slab interact via radiation pressure with the optical field of a high-finesse cavity.The reflectivity and transmission properties of a defect-free suspended PCS around normal incidence can be used to couple out-of-plane mechanical modes to an optical field by integrating it in a free-space cavity.Here we demonstrate the successful implementation of a PCS reflector on a high-tensile stress Si_(3)N_(4) nanomembrane.We illustrate the physical process underlying the high reflectivity by measuring the photonic-crystal band diagram.Moreover,we introduce a clear theoretical description of the membrane scattering properties in the presence of optical losses.By embedding the PCS inside a high-finesse cavity,we fully characterize its optical properties.The spectrally,angular-and polarization-resolved measurements demonstrate the wide tunability of the membrane’s reflectivity,from nearly 0 to 99.9470±0.0025%,and show that material absorption is not the main source of optical loss.Moreover,the cavity storage time demonstrated in this work exceeds the mechanical period of low-order mechanical drum modes.This so-called resolved-sideband condition is a prerequisite to achieve quantum control of the mechanical resonator with light.
文摘In this paper, we presented switching dynamic investigations on an InP photonic-crystal (PhC) nanocavity structure using homodyne pump-probe measurements. The measurements were compared with simulations based on temporal nonlinear coupled mode theory and carrier rate equations for the dynamics of the carrier density governing the cavity properties. The results provide insight into the nonlinear optical processes that govern the dynamics of nanocavities.
基金Project supported by the National Basic Research Program of China (Grant Nos. 2006CB806002 and 2010CB327604)the National High Technology Research and Development Program of China (Grant No. 2007AA03Z447)+3 种基金the National Natural Science Foundation of China (Grant Nos. 60838004 and 60678012)the Foundation for Key Program of Ministry of Education, China(Grant No. 108032)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 2007B34)the Program for New Century Excellent Talents in University of China (Grant No. NCET-07-0597)
文摘The filtering mechanism of a free output coupler mode-locked laser based on large-mode-area photonic-crystal fibre is analysed. A filtering-soliton mode-locked laser with 495 fs pulse width and 21 nJ pulse energy is achieved. Another novel cavity configuration is established to eliminate the filtering effect. Pulses, each 457 fs in width and 16.5 nJ in energy, are obtained in a soliton-like regime. Pulses, each 387 fs in width and 15.8 nJ in energy, are also generated in a stretched pulse regime and could be dechirped to 119 fs externally to the cavity.
文摘By using the complex finite element method (FEM) under perfectly matched layer (PML) boundary conditions, dispersion properties of microstructured optical fibres (MOFs) with elliptical air holes are analysed by changing the pitch and sizes of air holes belonging to the inner three rings. Meanwhile, the confinement loss of the fundamental mode is engineered to achieve the single-polarization single-mode transmission. Based on this analysis, a novel design of MOFs for properties of the single-polarization single-mode and the nearly zero ultraflattened dispersion between lpskm^-1 nm^-1 in the wavelength range of 1.2-1.6μm is presented for the first time.
基金The research leading to these results received funding from the European Research Council under the European Union’s Seventh Framework Programme(FP7/2007-2013)/ERC Grant Agreement No.[240460]the Thuringian Ministry of Education,Science and Culture under contract PE203-2-1(MOFA)and contract B514-10061(Green Photonics).FJ acknowledges financial support from the Abbe School of Photonics.
文摘Rare earth-doped fibres are a diode-pumped,solid-state laser architecture that is highly scalable in average power.The performance of pulsed fibre laser systems is restricted due to nonlinear effects.Hence,fibre designs that allow for very large mode areas at high average powers with diffraction-limited beam quality are of enormous interest.Ytterbium-doped,rod-type,large-pitch fibres(LPF)enable extreme fibre dimensions,i.e.,effective single-mode fibres with mode sizes exceeding 100 times the wavelength of the guided radiation,by exploiting the novel concept of delocalisation of higher-order transverse modes.The non-resonant nature of the operating principle makes LPF suitable for high power extraction.This design allows for an unparalleled level of performance in pulsed fibre lasers.