Terahertz wave switch based on silicon photonic crystals

Abstract

A compact and integrated terahertz (THz) wave photonic crystal switch is proposed in silicon. The switch operates based on a dynamic shift of the photonic bandgap by using an external applied electric field. The plane wave expansion method and the finite-difference time-domain method are used to verify and analyze the characteristics of the proposed THz wave switch. Numerical simulation results show that the THz wave switch has a high extinction ratio of 29.9 dB.

All-optical polarization-encoded negabinary signed-digit adder designs using terahertz-optical-asymmetric-demultiplexer switches

“…Owing to the benefits that photonics devices offer over its electronics counterparts, ultra response is promising along with huge increase in capacity (Mehra et al, 2012;Li et al, 2007;Stubkjaer, 2000;Schreicek et al, 2002;Vlachos et al, 2003). In the last decade and due to recent development in nonlinear optical materials, works and interests on optical computing have increased (Gosh et al, 2012;Gayen et al, 2011).…”

“…For instance, various schemes such as ultra-fast nonlinear interferometric and interferometric wavelength converters (Garai & Mukhopadhyay , 2010), semiconductor optical amplifier (SOA) waveguide based on a Michelson interferometer (Wang et al, 2006), and MachZehnder interferometric (MZI) (Zhang et al, 2003) were reported. Further, optical gates based on terahertz optical asymmetric demultiplexing (TOAD) including SOA as the nonlinear element have attracted many interests due to its practical advantages (Li et al, 2007;Gayan et al, 2011;Dimitiadou & Zoiros, 2012). Attractive features of TOAD switches such as the extremely high operational speed, tremendous potential for integration with a wide variety of active and passive components, low power consumption, and high stability motivates researchers to realize various all-optical logic operations such as XOR, OR, and NOR as well as arithmetic operations (Kim et al, 2006;Gayen & Roy, 2008;Roy & Gayen, 2007).…”

Metallic photonic crystals for terahertz tunable filters

“…Among these devices, photonic crystals (PCs) have proved to be an effective way to transmit and control THz waves [9][10][11]. PCs for high quality switching and filtering have been widely studied due to their potential applications [12][13][14]. For example, Ghattan et al [13] demonstrated the high density polyethylene (HDPE) PC with air holes filled with liquid crystal (LC) can be used as a switch for the sub-THz wave.…”

Hybrid add-drop filter based on one-dimensional photonic crystal Fabry-Perot resonator

“…This technology is applicable in optical communication systems and can be realized in silicon photonics for lasers, modulators, switches and filters [1][2][3][4][5][6][7]. One important application is the add-drop filter (ADF) [8][9][10][11][12] which is a device transferring data between two buses through the use of a resonator.…”