Experimental Investigation on the Quality Improvement of Low-Power Gain-Switching Diode Laser Picosecond Pulses using a Compact Highly Nonlinear Optical Loop Mirror Articles uri icon

publication date

  • May 2010

start page

  • 55004

issue

  • 5

volume

  • 49

International Standard Serial Number (ISSN)

  • 0091-3286

abstract

  • The experimental work presented in this paper investigates the quality improvement of gain-switched (GS) sources. GS is a straightforward technique to achieve short pulses from diode lasers; however, such
    pulses exhibit long duration (10&-100 ps),
    low power (in the milliwatt range), are asymmetric and are often
    generated along with pedestals or subpulses. Simultaneous compression
    and reshaping of these low quality pulses has been observed
    experimentally for several input power values. These effects have been
    achieved using a highly nonlinear optical-loop mirror, based on a
    microstructured optical fiber and a nonlinear semiconductor optical
    amplifier. It is designed to be compact and to directly process these
    complex pulses thus eliminating the requirement for prepulse
    conditioning. This offers overall benefits in terms of reduced system
    complexity. The quality of the pulses is characterized by their temporal
    width, pedestal height, duration, and spectral components. A maximum
    overall compression factor of 6 for a 10-mW
    average input power is observed. Additionally, the pulses obtained are
    observed to have improved quality for the input power range considered (500 muW to 30 mW,
    GS typical operational range) and the experimental scheme used
    preserves the compactness, efficiency, and simplicity of GS light
    sources.