Semiconductor laser with integral spatial mode filter

A semiconductor laser source comprising:

• a longitudinally extending body of semiconductor material having an optical cavity,
• a diverging gain region included in a portion of the body longitudinal extent and having a narrow input end and wider output end for achieving higher power output,
• a single spatial mode aperture region included in another portion of the body longitudinal extent optically coupled to said diverging gain region narrow input end,
• means to independently pump said diverging gain and single spatial mode aperture regions,
• a saturable absorbing region formed within a portion of said single spatial mode aperture region for mode-locking the operation of said laser source, and
• means to apply a reverse bias to said saturable absorbing region independently of said other regions.

A semiconductor laser source comprising:

• a longitudinally extending body of semiconductor material,
• a diverging gain region included in a portion of the body longitudinal extent and having a narrow input end and wider output end for achieving higher power output,
• a single spatial aperture region included in another portion of the body longitudinal extent optically coupled to said diverging gain region narrow input end, and
• means within said single spatial mode aperture region to mode lock the operation of said laser source,
• said diverging gain region comprising adjacently disposed diverging gain sections, means to electrically isolate and independently pump said adjacently disposed diverging sections.

A semiconductor laser source comprising:

• a longitudinally extending body of semiconductor material,
• a diverging gain region included in a portion of the body longitudinal extent and having a narrow input end and wider output end for achieving higher power output,
• a single spatial mode aperture region included in another portion of the body longitudinal extent optically coupled to said diverging gain region narrow input end,
• means to independently drive said single spatial mode aperture region to provide an optical oscillator and said diverging gain region to provide high power output,
• an optical cavity formed longitudinally in said coupled gain region and single spatial mode aperture region and extending externally of said semiconductor body to optical feedback means for said optical oscillator, and
• saturable absorber independent of said semiconductor body positioned within a portion of said optical cavity which is external of said semiconductor body, operation of said saturable absorber for mode locking operation of said laser source via pumping of either at least a portion of said diverging gain region or said single spatial mode aperture region at a period coinciding with the round trip transit time of light pulses in said optical cavity.