A dispersion-compensating square-lattice photonic crystal fiber for broadband compensation which covers the S, C and L communication bands, i.e. wavelength ranging from 1 460 nm to 1 625 nm is proposed in this paper. ...A dispersion-compensating square-lattice photonic crystal fiber for broadband compensation which covers the S, C and L communication bands, i.e. wavelength ranging from 1 460 nm to 1 625 nm is proposed in this paper. Theoretically, it is shown a negative dispersion coefficient of about-595 ps/(nm·km) to-1 288 ps/(nm·km) over S to L bands and-975 ps/(nm·km) at the operating wavelength 1 550 nm. The relative dispersion slope is perfectly matched to that of conventional single-mode fiber of about 0.003 6 nm^(-1). Besides the proposed photonic crystal fiber shows the large nonlinear coefficient of 61.88 W/km at the operating wavelength of 1 550 nm. Moreover, the variation of structural parameters is also studied and discussed here.展开更多
This work demonstrates the atomic vacancy effects on the phonon properties of armchair silicene nanoribbon in a step by step process for the first time.The phonon localization effect figures out the fact that vacancie...This work demonstrates the atomic vacancy effects on the phonon properties of armchair silicene nanoribbon in a step by step process for the first time.The phonon localization effect figures out the fact that vacancies cause to high-energy phonons become localized,whereas low-energy phonons can easily transmit.The vacancy reduces high-energy phonon transmission severely compared to low-energy phonon.It is also found from phonon density of states that high-frequency phonons soften towards the low-frequency region.The simulated phonon bandstructure verifies that most of the phonon branches transform to a nondegenerate state from a degenerate state and shifted toward a lower frequency regime due to the presence of vacancies.The overall consequences of atomic vacancies on the phonon thermal conductance disclose the reality that only a few atomic vacancies result in a vital reduction of phonon thermal conductance.In addition,the entropy of the disordered system is investigated.展开更多
文摘A dispersion-compensating square-lattice photonic crystal fiber for broadband compensation which covers the S, C and L communication bands, i.e. wavelength ranging from 1 460 nm to 1 625 nm is proposed in this paper. Theoretically, it is shown a negative dispersion coefficient of about-595 ps/(nm·km) to-1 288 ps/(nm·km) over S to L bands and-975 ps/(nm·km) at the operating wavelength 1 550 nm. The relative dispersion slope is perfectly matched to that of conventional single-mode fiber of about 0.003 6 nm^(-1). Besides the proposed photonic crystal fiber shows the large nonlinear coefficient of 61.88 W/km at the operating wavelength of 1 550 nm. Moreover, the variation of structural parameters is also studied and discussed here.
文摘This work demonstrates the atomic vacancy effects on the phonon properties of armchair silicene nanoribbon in a step by step process for the first time.The phonon localization effect figures out the fact that vacancies cause to high-energy phonons become localized,whereas low-energy phonons can easily transmit.The vacancy reduces high-energy phonon transmission severely compared to low-energy phonon.It is also found from phonon density of states that high-frequency phonons soften towards the low-frequency region.The simulated phonon bandstructure verifies that most of the phonon branches transform to a nondegenerate state from a degenerate state and shifted toward a lower frequency regime due to the presence of vacancies.The overall consequences of atomic vacancies on the phonon thermal conductance disclose the reality that only a few atomic vacancies result in a vital reduction of phonon thermal conductance.In addition,the entropy of the disordered system is investigated.