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Normal modes of N coupled lasers.

W J Fader, G E Palma

|September 3, 2009

Summary

This summary is machine-generated.

This study derives normal modes for coupled lasers, finding that frequency spacing increases with coupling but decreases with more lasers (N). Optimal coupling configurations are crucial for mode selection in laser arrays.

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Area of Science:

Laser physics
Quantum optics
Array optics

Background:

Coupled laser systems are fundamental in various optical applications.
Understanding the normal modes and eigenfrequencies is key to controlling laser output.
Previous models often simplified coupling configurations or laser numbers.

Purpose of the Study:

To derive the normal modes for an arbitrary number (N) of longitudinally coupled lasers.
To analyze the impact of coupling configurations on eigenfrequencies, phases, and amplitudes.
To investigate the relationship between frequency spacing, coupling strength, and the number of lasers for mode selection.

Main Methods:

Derivation of normal modes using a weak-coupling model.
Analysis of eigenfrequencies, relative phases, and amplitudes for different coupling schemes.

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Mathematical modeling of frequency spacing as a function of coupling and N.

Main Results:

Eigenfrequencies and laser parameters were obtained from the weak-coupling model.
Frequency spacing increases with coupling strength.
Frequency spacing diminishes with an increasing number of lasers (N).
Specific coupling configurations (all-to-all vs. nearest-neighbor) exhibit distinct frequency spacing behaviors as N increases.

Conclusions:

The derived normal modes provide insights into the behavior of coupled laser arrays.
Frequency spacing is a critical factor for mode selection, influenced by coupling and N.
Nearest-neighbor coupling leads to rapid zero-spacing with increasing N, while all-to-all coupling shows a slower decrease.