Self-localized structures in vertical-cavity surface-emitting lasers with external feedback

Area of Science:

• Physics
• Optics
• Nonlinear Dynamics

Background:

• Broad area vertical-cavity surface-emitting lasers (VCSELs) are crucial semiconductor devices.
• Understanding their behavior under optical feedback is essential for device optimization.
• Cavity solitons are localized nonlinear states with unique properties.

Purpose of the Study:

• To analyze the spatio-temporal regimes of broad area VCSELs with frequency-selective optical feedback.
• To investigate the existence and dynamical properties of cavity solitons in these systems.
• To construct the bifurcation diagram for stationary self-localized states.

Main Methods:

• Modeling of broad area VCSELs subjected to frequency-selective optical feedback.
• Analysis of spatio-temporal regimes above the lasing threshold.
• Construction of bifurcation diagrams for stationary self-localized states.

Main Results:

• Branches of cavity solitons emerge from degenerate Hopf bifurcations.
• These soliton branches collide in a saddle-node bifurcation.
• A maximum pump current for soliton existence is found below the laser's threshold without feedback.

Conclusions:

• The study elucidates the formation and existence conditions of cavity solitons in VCSELs with optical feedback.
• The predicted properties of cavity solitons align well with experimental observations.
• This research contributes to the fundamental understanding and potential applications of VCSELs.