Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Carrier Generation and Recombination

Carrier Generation and Recombination

Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Vertically tapered waveguide spot size converters fabricated via a linewidth controlled grey tone lithography for InP-based photonic integrated circuits.

Optics express·2020

Same author

Quantum dots for terahertz generation.

Journal of physics. Condensed matter : an Institute of Physics journal·2011

Same author

Rectangular characteristic gratings for waveguide input and output coupling.

Applied optics·2010

Same author

Modified integrated optic Fresnal lens for waveguide-to-fiber coupling.

Applied optics·2010

Same author

Model for the effects of material shrinkage on volume holograms.

Applied optics·2010

Same author

Computer modeling of the effects of apertures in the Fourier-transform plane of Fourier-transform imaging systems.

Applied optics·2010

Search research articles

Related Experiment Video

Updated: Jul 9, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

Published on: July 12, 2017

Two-photon absorption-induced self-phase modulation in GaAs-AlGaAs waveguides for surface-emitted second-harmonic

T G Ulmer¹, R K Tan, Z Zhou

¹School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0250, USA.

|December 13, 2007

Summary

Asymmetric spectral distortion in GaAs-AlGaAs waveguides is caused by free carrier accumulation from two-photon absorption. This finding impacts surface-emitted second-harmonic generation device design.

More Related Videos

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing

Published on: December 3, 2013

Related Experiment Videos

Last Updated: Jul 9, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

Published on: July 12, 2017

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing

Published on: December 3, 2013

Area of Science:

Optoelectronics
Semiconductor Physics
Nonlinear Optics

Background:

Surface-emitted second-harmonic generation (SE-SHG) is crucial for frequency conversion.
GaAs-AlGaAs multilayer waveguides are key components in SE-SHG devices.
Pulse distortion can limit the efficiency and performance of optical devices.

Purpose of the Study:

Investigate the cause of asymmetric spectral distortion in fundamental pulses.
Analyze the impact of free carrier generation on waveguide performance.
Validate simulation models for nonlinear optical effects in waveguides.

Main Methods:

Experimental transmission of fundamental pulses through GaAs-AlGaAs multilayer waveguides.
Spectroscopic analysis of transmitted pulses to identify spectral distortions.
Numerical simulations incorporating two-photon absorption (TPA) and free carrier effects.
Measurement of the TPA coefficient in GaAs layers.

Main Results:

Observed significant asymmetric distortion in the spectra of transmitted fundamental pulses.
Attributed distortion to refractive index changes caused by free carrier accumulation.
Free carriers are generated via two-photon absorption in the GaAs layers.
Numerical simulations accurately reproduced experimental spectral distortions.

Conclusions:

Two-photon absorption in GaAs layers is the primary cause of performance-limiting spectral distortion.
Free carrier dynamics significantly influence the nonlinear optical response of these waveguides.
Accurate modeling of TPA and free carrier effects is essential for designing efficient SE-SHG devices.