Method of achieving acceptable performance in and fabrication of a monolithic photonic integrated circuit (PIC) with integrated arrays of laser sources and modulators employing an extended identical active layer (EIAL)

A method of providing multiple signal channels in the same photonic integrated circuit on a single semiconductor chip comprising the steps of:

• providing a modulated source in each signal channel, each modulated source comprising a laser source having a different laser emission wavelength and an external modulator;
• extending an active region of the chip to include all of the signal channels to form an extended identical active layer (EIAL) so that the multiple laser sources and modulators share the EIAL;
• and
• detuning the laser emission wavelength in each laser source within the EIAL from the laser active region wavelength;
• providing an arrayed waveguide grating that is coupled to each of the modulators,
• wherein the laser emission wavelength of said each modulated source has a corresponding positively detuned offset, which is different from one another, such that the laser emission wavelength of said each modulated source is greater than an identical active region wavelength of a respective one of the modulated sources.

A method of providing an optical circuit on a single semiconductor chip, the method comprising:

• providing a first modulated source in the optical circuit, the first modulated source including a first laser and a first modulator, the first laser configured to supply first light having a first wavelength;
• providing a second modulated source in the optical circuit, the second modulated source including a second laser and a second modulator, the second laser configured to supply second light at a second wavelength;
• providing an active region such that one of the first laser, the second laser, the first modulator, and the second modulator includes a first portion of the active region, and another one of the first laser, the second laser, the first modulator, and the second modulator includes a second portion of the active region, the first and second portions of the active region forming an extended identical active layer (EIAL),
• wherein a laser emission wavelength of each said first and second modulated sources has a corresponding detuned offset, which is different from one another, such that laser emission wavelength of each said first and second modulated sources is greater than an active region wavelength of a respective one of the first and second modulated sources.