Photonic crystal fibers （PCFs） with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index differen...Photonic crystal fibers （PCFs） with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index difference between the index of the core and the effective index of the cladding, we improve the characteristic parameters such as numerical aperture and V-parameter, and reduce its bending loss to about one tenth of a conventional PCF. Implementing such a structure in PCFs may be one step forward to achieve low loss PCFs for communication applications.展开更多
The effects of high drawing speeds on parameters of holey fibers are presented. A holey fiber preform structure was made by using tube-in-tube method and was drawn at high speeds with an aim of mass production to meet...The effects of high drawing speeds on parameters of holey fibers are presented. A holey fiber preform structure was made by using tube-in-tube method and was drawn at high speeds with an aim of mass production to meet the demand of next generation communication systems. Transmission parameters such as numerical aperture and normalized frequency of the fabricated holey fibers have been measured and compared with theoretical values based on effective index method. Although the fabricated holey fibers were not of high quality, the analyses of the parameters have shown promising outlook for fabrication of such fibers.展开更多
Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial...Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.展开更多
An analysis of splice loss between photonic crystal fibers （PCFs） and conventional single-mode fibers （SMFs） is presented at bending and straight conditions, by using scalar effective index method （SEIM）, vector...An analysis of splice loss between photonic crystal fibers （PCFs） and conventional single-mode fibers （SMFs） is presented at bending and straight conditions, by using scalar effective index method （SEIM）, vectorial effective index method （VEIM）, and finite-difference frequency domain （FDFD） methods. It is shown that when there is a slight bending at the vicinity of splice joint, the spot size increases sharply at higher frequencies. On the basis of the obtained results, a mechanism to optimize the splice loss between PCFs and conventional SMFs, both with any geometry, is suggested. The results can be utilized for PCF- based devices to be jointed to SMF as a transmission medium.展开更多
文摘Photonic crystal fibers （PCFs） with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index difference between the index of the core and the effective index of the cladding, we improve the characteristic parameters such as numerical aperture and V-parameter, and reduce its bending loss to about one tenth of a conventional PCF. Implementing such a structure in PCFs may be one step forward to achieve low loss PCFs for communication applications.
文摘The effects of high drawing speeds on parameters of holey fibers are presented. A holey fiber preform structure was made by using tube-in-tube method and was drawn at high speeds with an aim of mass production to meet the demand of next generation communication systems. Transmission parameters such as numerical aperture and normalized frequency of the fabricated holey fibers have been measured and compared with theoretical values based on effective index method. Although the fabricated holey fibers were not of high quality, the analyses of the parameters have shown promising outlook for fabrication of such fibers.
文摘Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.
基金support of the Iran Telecom Research Center for Project 8631351
文摘An analysis of splice loss between photonic crystal fibers （PCFs） and conventional single-mode fibers （SMFs） is presented at bending and straight conditions, by using scalar effective index method （SEIM）, vectorial effective index method （VEIM）, and finite-difference frequency domain （FDFD） methods. It is shown that when there is a slight bending at the vicinity of splice joint, the spot size increases sharply at higher frequencies. On the basis of the obtained results, a mechanism to optimize the splice loss between PCFs and conventional SMFs, both with any geometry, is suggested. The results can be utilized for PCF- based devices to be jointed to SMF as a transmission medium.
