Monolithically integrated InP electro-optically tunable ring laser, a laser device as well as a corresponding method

A method of operating a tunable ring laser, wherein the method comprises:

• coupling, by a power coupler, a first light wave and a second light wave in a ring resonator;
• guiding, by the ring resonator and a phase modulator, a first light wave and a second light wave via at least one of a waveguide of the ring resonator or a waveguide of the phase modulator respectively, wherein a cross section of the waveguide of at least one of the ring resonator or the phase modulator respectively is configured as an electro-refractive modulator,
• applying, to at least one of the waveguide of the ring resonator or the waveguide of the phase modulator respectively, a reverse bias voltage to tune the tunable ring laser, and
• reflecting, by a reflector, an anti-clock-wise mode or a clock-wise mode, such that a propagation direction of a mode of the tunable ring laser is unidirectional.

A method of fabricating a tunable ring laser having a ring cavity, the method comprising:

• at least partly providing a ring resonator having a waveguide;
• at least partly providing a phase modulator having a waveguide;
• at least partly providing a power coupler coupled to the resonator;
• and
• at least partly providing a reflector to reflect an anti-clock-wise mode or a clock-wise mode, such that a propagation direction of a mode of the tunable ring laser is unidirectional,
• wherein a cross section of the waveguide of at least one of the ring resonator or the phase modulator is configured as an electro-refractive modulator such that the tunable ring laser is tunable by applying a reverse bias voltage to at least one of the waveguide of the ring resonator or the waveguide of the phase modulator respectively.