scholarly journals Ultrafast All-Optical Switch with an Operational Speed Unlimited by the Slow Relaxation of a High Efficiency Nonlinear Refractive Index Change.

1995 ◽  
Vol 23 (11) ◽  
pp. 988-995
Author(s):  
Kazuhito TAJIMA ◽  
Shigeru NAKAMURA
1990 ◽  
Vol 29 (3) ◽  
pp. 191 ◽  
Author(s):  
Takeshi Kato ◽  
Hiroaki Inoue ◽  
Yasushi Takahashi ◽  
Koji K. Ishida

2005 ◽  
Vol 30 (11) ◽  
pp. 1261 ◽  
Author(s):  
Hernando Garcia ◽  
Anthony M. Johnson ◽  
Ferdinand A. Oguama ◽  
Sudhir Trivedi

2015 ◽  
Vol 29 (05) ◽  
pp. 1550024 ◽  
Author(s):  
Li Zhang

Based on the compact density matrix approach, the linear and nonlinear refractive index change (RIC) and optical rectification (OR) coefficients in a GaN -based step QW with strong built-in electric field (BEF) have been theoretically deduced and investigated in detail. The analytical electronic state is derived by the two airy functions. And the band nonparabolicity is taken into account by using an energy dependence effective mass (EDEM) method. Numerical calculations on a four-layer AlN / GaN / Al x Ga 1-x N / AlN step QW are performed, and the curves for the geometric factors, the linear, the nonlinear, the total RICs and the OR coefficients as functions of the structural parameters of the step QW are discussed. The features for these curves were specified and reasons for the features were explained reasonably. It is found that the decreasing of well width Lw, and step barrier width Lb and the doped concentration x in step barrier will result in the significant enhancement of the RICs. With the decrease of Lw, Lb and x, the resonant photon energies of RIC and OR coefficients have obvious blue-shift. Moreover, the RIC and OR coefficients behave different dependence on the structural parameters of the GaN -based step QWs. The profound physical reasons are also analyzed.


2007 ◽  
Vol 31 ◽  
pp. 206-208 ◽  
Author(s):  
Tetsuya Mizumoto ◽  
Yoichi Akano ◽  
Kazuhiko Tamura ◽  
Masaki Yoshimura

A pump-induced refractive index change was measured in a passive GaInAsP waveguide together with its temporal response. Also, the temporal response of distributed feedback (DFB) waveguide transmittance modulated by the pump-induced index change was experimentally investigated for an application to all-optical switching devices.


1993 ◽  
Vol 02 (03) ◽  
pp. 415-436 ◽  
Author(s):  
E.R. YOUNGDALE ◽  
J.R. MEYER ◽  
C.A. HOFFMAN ◽  
F.J. BARTOLI ◽  
W.I. WANG

We derive explicit criteria for the properties required of a semiconductor nonlinear medium suitable for use in all-optical switching devices employing total internal reflection. Transmission as a function of laser intensity and film thickness has been calculated using a realistic model for penetration of the evanescent beam under TIR conditions. Requirements based on these results include a large nonlinear refractive index, large index change at saturation and small absorption coefficient. We show that unlike previously-studied semimetals and narrow-gap semiconductors, Type-II superlattices such as InAs-GaSb and variable-overlap superlattices (variants of Type-II which include a spacer between the layer containing the conduction-band minimum and that containing the valence band maximum) such as InAs-AlSb-GaSb hold prospects for satisfying all of these requirements simultaneously. As the free carrier lifetime will have a crucial influence on device performance, we have initiated a systematic experimental study of electron-hole recombination in InAs-based superlattices. From degenerate and nondegenerate four-wave mixing experiments, we have also determined nonlinear optical coefficients as a function of difference frequency and intensity. An InAs-GaSb superlattice has been found to display a refractive index change of ≈ 0.1, as well as device figures of merit which slightly surpasses any previously reported for weakly-saturating nonlinearities at CO 2 wavelengths. It is anticipated that future experiments on Type-II superlattices with longer lifetimes may yield nearly two orders of magnitude additional improvement in the nonlinear refractive index.


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