All-optical switching in silicon photonic crystal waveguides by use of the plasma dispersion effect

Abstract

Silicon photonic crystals offer new ways of controlling the propagation of light as well as new tools for the realization of high-density optical integration on monolithic substrates. However, silicon does not possess the strong nonlinearities that are commonly used in the dynamic control of optical devices. Such dynamic control is nevertheless essential if silicon is to provide the higher levels of functionality that are required for optical integration. We demonstrate that the combination of the refractive index change caused by the presence of photoexcited carriers, or so-called plasma dispersion, and photonic crystal properties such as photonic bandgaps, constitutes a powerful tool for active control of light in silicon integrated devices. We show close to 100% modulation depth near the photonic crystal band edge.

Optically tunable silicon photonic crystal microcavities

“…The characterization set up was the same as that used in Ref. [1]. Figure 2 shows the measured transmission spectra of three experimental samples of increasing cavity length d. The peak of the cavity resonance shifts to longer wavelengths with increasing cavity length.…”

“…In a previous publication, [1] we demonstrated an all-optical modulation scheme based on the concept of shifting the transmission band-edge of a photonic crystal waveguide. The modulation resulted from a negative change in the refractive index of silicon caused by carriers generated by an optical pump.…”

Design of all-optical switching component based on pillar-array hybrid nonlinear photonic crystal cavity

“…Among several switching schemes that have been explored in the past years [1][2][3][4][5], photonic crystals (PCs) have been shown to be a promising candidate for this purpose since this concept was first proposed by Scalora in 1994 [6][7][8][9]. Among several switching schemes that have been explored in the past years [1][2][3][4][5], photonic crystals (PCs) have been shown to be a promising candidate for this purpose since this concept was first proposed by Scalora in 1994 [6][7][8][9].…”

Optical and Local Tuning of Planar Photonic Crystals Infiltrated with Organic Molecules

“…In this field, the potential of nematic liquid crystal (LC) infiltration has already been demonstrated and several tuning mechanisms have been explored, including for example temperature tuning [2] and electrical tuning [3]. Nevertheless, while it has been shown that all-optical tuning of semiconductor-based PhCs may have applications in various fields [4], little has been done on the optical tuning of infiltrated PhCs [5]. Moreover, the local tuning of planar PhC devices is emerging as a viable approach to realize real tunable devices [6].…”