High coherent power, two-dimensional surface-emitting semiconductor diode array laser

A semiconductor laser comprising:

• (a) a semiconductor substrate;
• (b) an array of laterally-spaced laser device elements formed on the substrate, each of the laser device elements extending in a longitudinal direction on the substrate, each laser device element including a second order distributed feedback grating having optical gain which has a chirped period that corresponds to a phase shift distributed across the grating, and each laser device element having distributed Bragg reflector gratings bounding the distributed feedback grating in the longitudinal direction to reflect light back to the distributed feedback grating and which also have chirped periods which correspond to distributed phase shifts;
• (c) electrodes by which voltage can be applied across the array and the substrate, and means for directing current to a region of the array containing the distributed feedback gratings of the laser device elements;
• and
• (d) laser device interelement regions on the substrate between the device elements, the device elements in which the distributed feedback grating and the distributed Bragg reflector gratings are formed having a lower effective refractive index than the index of the interelement regions, the interelement regions spacing the device elements by a width such that light propagating laterally from the device elements is fully transmitted between adjacent device elements to form a laterally resonant antiguided array for which the device elements are substantially equally coupled to each other, the interelement regions having strong light absorption to provide discrimination of modes with significant interelement field.

A semiconductor laser comprising:

• (a) a semiconductor substrate;
• (b) an array of laterally-spaced laser device elements formed on the substrate, each of the laser device elements extending in a longitudinal direction on the substrate, each laser device element including a second order distributed feedback grating having optical gain, and each laser device element having distributed Bragg reflector gratings bounding the distributed feedback grating in the longitudinal direction to reflect light back to the distributed feedback grating;
• (c) electrodes by which voltage can be applied across the array and the substrate, and means for directing current to a region of the array containing the distributed feedback gratings of the laser device elements;
• (d) laser device interelement regions on the substrate between the device elements, the device elements in which the distributed feedback grating and the distributed Bragg reflector gratings are formed having a lower effective refractive index than the index of the interelement regions, the interelement regions spacing the device elements by a width such that light propagating laterally from the device elements is fully transmitted between adjacent device elements to form a laterally resonant antiguided array for which the device elements are substantially equally coupled to each other, the interelement regions having strong light absorption to provide discrimination of modes with significant interelement field;and
• (e) a π phase shifting film formed on the substrate at an emission window of the substrate by which light is emitted covering about one half of the emission window to provide a π phase shift and substantially single lobe emission from the emission window of the semiconductor substrate.

A surface emitting semiconductor array laser comprising:

• (a) a semiconductor substrate;
• (b) a two-dimensional array of at least four laser array devices formed on and arranged adjacent to one another on the substrate, the laser array devices spaced from one another by interdevice regions so that each laser array device is coupled to at least two other laser array devices which are displaced therefrom both laterally and longitudinally, wherein the laser array devices are spaced from one another laterally by the interdevice regions by a spacing width and index of refraction that allows full transmission of light generated in each of the laser array devices to adjacent laser array devices as coupled through the interdevice regions on the substrate, each laser array device comprising:
• (1) an array of laterally-spaced laser device elements formed on the substrate, each of the laser device elements extending in a longitudinal direction on the substrate, each laser device element including a second order distributed feedback grating having optical gain, and distributed Bragg reflector gratings bounding the distributed feedback grating in the longitudinal direction to reflect light back to the distributed feedback grating,
• (2) electrodes by which voltage can be applied across the array of laterally-spaced laser device elements and the substrate, and means for directing current to a region of the array containing the distributed feedback gratings of the laser device elements;
• (3) laser device interelement regions on the substrate between the device elements, the device elements in which the distributed feedback grating and the distributed Bragg reflector gratings are formed having a lower effective refractive index than the index of the interelement regions, the interelement regions spacing the device elements by a width such that light propagating laterally from the device elements is fully transmitted between adjacent device elements to form a laterally resonant antiguided array for which the device elements are substantially equally coupled to each other;
• and
• (4) π phase shifting films formed on the substrate at the emission windows of the substrate by which light is emitted from each laser array device, covering about one-half of each emission window to provide a π phase shift and substantially single lobe emission from each emission window of the semiconductor substrate.