Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

All optical switching and continuum generation in silicon waveguides

Open Access Open Access

Abstract

First demonstration of cross phase modulation based interferometric switch is presented in silicon on insulator waveguides. By using Mach-Zehnder interferometric configuration we experimentally demonstrate switching of CW signal ~25 nm away from the pump laser. We present the effect of free carrier accumulation on switching. Additionally, we theoretically analyze the transient effects and degradations due to free carrier absorption, free carrier refraction and two photon absorption effects. Results suggest that at low peak power levels the system is governed by Kerr nonlinearities. As the input power levels increase the free carrier effects becomes dominant. Effect of free carrier generation on continuum generation and power transfer also theoretically analyzed and spectral broadening factor for high input power levels is estimated.

©2004 Optical Society of America

Full Article  |  PDF Article
More Like This
Influence of nonlinear absorption on Raman amplification in Silicon waveguides

R. Claps, V. Raghunathan, D. Dimitropoulos, and B. Jalali
Opt. Express 12(12) 2774-2780 (2004)

Time-resolved study of Raman gain in highly confined silicon-on-insulator waveguides

Qianfan Xu, Vilson R. Almeida, and Michal Lipson
Opt. Express 12(19) 4437-4442 (2004)

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (8)

Fig. 1.
Fig. 1. Experimental setup of XPM based silicon switch. Mach Zehnder interferometer is used for switching. XPM induced phase shift causes switching of CW signal to the output port.
Fig. 2.
Fig. 2. Output results of XPM based silicon switch. a) Residual pump pulse and switched CW signal when probe signal is present. b) Net switching results. Exponential decay indicates free carrier refraction.
Fig. 4.
Fig. 4. Total amount of phase shift for two different free carrier lifetime values induced by a) the index change due to free carrier accumulation and b) the Kerr nonlinearity. T=pulse period and τeff=free carrier life time.
Fig. 5.
Fig. 5. Total amount of phase shift induced by the index change due to free carrier accumulation and the Kerr nonlinearity in the absence of free carrier accumulation. 180° phase shift can be obtained by Kerr nonlinearity at moderate power levels and with minimal free carrier effect.
Fig. 6.
Fig. 6. Simulated switching behavior in silicon. a) full scale representation b) 30ps time window of switched signal. Perfect switching profile is obtained at 40W peak power levels.
Fig. 7.
Fig. 7. a) Qualitative depiction of free carrier transients in the time scale of optical pulse. The free carrier density follows the integral of pulse shape. b) Simulated results of spectral broadening factor.
Fig. 8.
Fig. 8. Spectrum generated at ~25 GW/cm2. SPM generates symmetric spectral broadening and free carrier refraction generate blue shifted spectrum.
Fig. 9.
Fig. 9. Power transfer function in the presence of pulse steepening. Free carrier absorption causes higher attenuation at the trailing edge of the pulse and average throughput reduces On the other hand peak power level shows saturated behavior due to TPA.

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

E ( t , z ) z = 1 2 ( α + Δ α + α TPA ) E ( t , z ) i g γ E p ( t , z ) 2 E + i 2 π λ Δ n E ( t , z )
Δ α = e 3 λ 2 4 π 2 c 3 ε 0 n [ Δ N e m ce · μ e + Δ N h m ch · μ h ]
Δ n = e 2 λ 2 8 π 2 c 2 ε 0 n [ Δ N e m ce + Δ N h m ch ]
N ( t , z ) t = N ( t , z ) τ eff + β I p ( t ) 2 2 ω
α TPA = 4 n 480 π A eff 2 β I p ( t , z )
Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved