A novel scheme for the design of an ultra-compact and high-performance optical switch is proposed and investigated numerically. Based on a standard silicon(Si) photonic stripe waveguide, a section of hyperbolic metama...A novel scheme for the design of an ultra-compact and high-performance optical switch is proposed and investigated numerically. Based on a standard silicon(Si) photonic stripe waveguide, a section of hyperbolic metamaterials(HMM) consisting of 20-pair alternating vanadium dioxide (VO_2)∕Si thin layers is inserted to realize the switching of fundamental TE mode propagation. Finite-element-method simulation results show that, with the help of an HMM with a size of 400 nm × 220 nm × 200 nm(width × height × length), the ON/OFF switching for fundamental TE mode propagation in an Si waveguide can be characterized by modulation depth(MD) of5.6 d B and insertion loss(IL) of 1.25 dB. It also allows for a relatively wide operating bandwidth of 215 nm maintaining MD > 5 dB and IL < 1.25 dB. Furthermore, we discuss that the tungsten-doped VO_2 layers could be useful for reducing metal-insulator-transition temperature and thus improving switching performance. In general, our findings may provide some useful ideas for optical switch design and application in an on-chip all-optical communication system with a demanding integration level.展开更多
The basic idea of the finite element beam propagation method （FE-BPM） is described. It is applied to calculate the fundamental mode of a channel plasmonic polariton （CPP） waveguide to confirm its validity. Both th...The basic idea of the finite element beam propagation method （FE-BPM） is described. It is applied to calculate the fundamental mode of a channel plasmonic polariton （CPP） waveguide to confirm its validity. Both the field distribution and the effective index of the fundamental mode are given by the method. The convergence speed shows the advantage and stability of this method. Then a plasmonic waveguide with a dielectric strip deposited on a metal substrate is investigated, and the group velocity is negative for the fundamental mode of this kind of waveguide. The numerical result shows that the power flow direction is reverse to that of phase velocity.展开更多
基金Ministry of Science and Technology of the People's Republic of China(MOST)(2016YFA0301300)National Natural Science Foundation of China(NSFC)(61275201,61372037)+2 种基金Beijing University of Posts and Telecommunications(BUPT)Excellent Ph.D.Students Foundation(CX2016204)Fundamental Research Funds for the Central Universities(2016RC24)Beijing Excellent Ph.D.Thesis Guidance Foundation(20131001301)
文摘A novel scheme for the design of an ultra-compact and high-performance optical switch is proposed and investigated numerically. Based on a standard silicon(Si) photonic stripe waveguide, a section of hyperbolic metamaterials(HMM) consisting of 20-pair alternating vanadium dioxide (VO_2)∕Si thin layers is inserted to realize the switching of fundamental TE mode propagation. Finite-element-method simulation results show that, with the help of an HMM with a size of 400 nm × 220 nm × 200 nm(width × height × length), the ON/OFF switching for fundamental TE mode propagation in an Si waveguide can be characterized by modulation depth(MD) of5.6 d B and insertion loss(IL) of 1.25 dB. It also allows for a relatively wide operating bandwidth of 215 nm maintaining MD > 5 dB and IL < 1.25 dB. Furthermore, we discuss that the tungsten-doped VO_2 layers could be useful for reducing metal-insulator-transition temperature and thus improving switching performance. In general, our findings may provide some useful ideas for optical switch design and application in an on-chip all-optical communication system with a demanding integration level.
基金the National Natural Science Foundation of China under Grant No.60707009.
文摘The basic idea of the finite element beam propagation method （FE-BPM） is described. It is applied to calculate the fundamental mode of a channel plasmonic polariton （CPP） waveguide to confirm its validity. Both the field distribution and the effective index of the fundamental mode are given by the method. The convergence speed shows the advantage and stability of this method. Then a plasmonic waveguide with a dielectric strip deposited on a metal substrate is investigated, and the group velocity is negative for the fundamental mode of this kind of waveguide. The numerical result shows that the power flow direction is reverse to that of phase velocity.
