Fabry-Perot laser with wavelength control

Method of producing optical radiation with a desired mode structure, comprising:

• producing an optical waveguide capable of propagating said optical radiation;
• forming in said optical waveguide a sub-cavity with a predetermined length, said sub-cavity producing a sub-cavity mode structure that overlaps with the desired mode structure;
• and
• forming along said optical waveguide an aperiodic filter having contrast elements, said aperiodic filter filtering the sub-cavity mode structure to generate the desired mode structure, by the acts of:
• defining a cost function representing a goodness of fit between the desired mode structure and an actual spectral response of the filter;
• assigning to each contrast element of the aperiodic filter at least one characteristic attribute;
• generating an initial arrangement of the contrast elements along the optical waveguide;
• iteratively modifying at least one characteristic attribute of at least one of the contrast elements and computing for each iteration a cost function;
• if the computed cost function for an iteration is less than a predetermined cost function value, selecting a corresponding arrangement of the contrast elements as a desired arrangement of the contrast elements to provide said desired mode structure.

A laser device comprising:

• a laser cavity comprising an optical waveguide and facets;
• a sub-cavity within said laser cavity and between said facets;
• and
• a plurality of contrast elements adjacent said sub-cavity and having predetermined inter-element separations and predetermined spacings relative to said sub-cavity so that said contrast elements interact with said optical waveguide and form an aperiodic grating to produce a filtering function for optical radiation propagating in said optical waveguide.