Tunable laser device for avoiding optical mode hops

A method of fabricating an integrated semiconductor device, comprising:

• forming on a semiconductor substrate a wavelength-tunable laser having a grating section adjacent to a gain section, the grating section having an active layer and a current-induced grating which modulates gain in the active layer in the direction of light propagation, and the gain section having an active layer, the grating section and the gain section consisting a laser cavity emitting light at a wavelength determined by the current-induced grating localized only within the grating section wherein the current-induced grating provides periodic modulation of the gain of the active layer and periodic modulation of a differential refractive index between the different indices of the active layer and of the current-induced grating;
• forming a first electrical contact over the grating section for providing current to the grating section to control the wavelength of light emitted from the laser;
• and
• forming a second electrical contact over the gain section for providing current to the gain section to control the output power of the light.

An integrated semiconductor device, comprising:

• a semiconductor substrate;
• a wavelength-tunable laser on the substrate comprising a grating section adjacent to a gain section, the grating section having an active layer and a grating with a coupling strength product κL greater than 1.5, where κ is a coupling coefficient and L is a length of a laser cavity, and the gain section having an active layer, the grating section and the gain section consisting the laser cavity having the length L emitting light at a wavelength determined by the current-induced grating localized only within the grating section wherein the current-induced grating provides periodic modulation of the gain of the active layer in the direction of light propagation and provides periodic modulation of a differential refractive index between the different indices of the active layer and of the current-induced grating;
• a first electrical contact over the grating section for providing current to the grating section to control the wavelength of light emitted from the laser;
• and
• a second electrical contact over the gain section for providing current to the gain section to control the otuput power of the light.

A method of fabricating an integrated semiconductor device, comprising:

• forming on a semiconductor substrate a wavelength-tunable laser having a grating section adjacent to a gain section, the grating section having an active layer and a grating with a coupling strength product κL greater than 1.5, where κ is a coupling coefficient and L is a length of a laser cavity, and the gain section having an active layer, the grating section and the gain section consisting the laser cavity having the length L emitting light at a wavelength determined by the current-induced grating localized only within the grating section wherein the current-induced grating provides periodic modulation of the gain of the active layer in the direction of light propagation and provides periodic modulation of a differential refractive index between the different indices of the active layer and of the current-induced grating;
• forming a first electrical contact over the grating section for providing current to the grating section to control the wavelength of light emitted from the laser;
• and
• forming a second electrical contact over the gain section for providing current to the gain section to control the output power of the light.