Acousto-optic based broadband directional optical device

A directional optical device, comprising:

• a tapered waveguide structure configured to receive a first optical wave in a first optical mode at a first end of the waveguide structure, and
• an array of a plurality of acoustic wave transducers, wherein the array is placed at a distance to the waveguide structure and is configured to:
• generate a first plurality of acoustic waves, each acoustic wave having a phase that results in a first set of phase differences between the first plurality of acoustic waves, and
• provide the first plurality of acoustic waves to the waveguide structure,
• wherein the first plurality of acoustic waves creates a parabolic intensity profile on the waveguide structure,
• wherein the waveguide structure is configured, due to the tapering of the waveguide structure, to change a wavevector of the first optical wave as it propagates through a tapered first section of the waveguide structure,
• wherein the first plurality of acoustic waves is configured, due to the first set of phase differences between the first plurality of acoustic waves and the parabolic intensity profile, to induce a momentum-shift and a frequency-shift in the first optical wave propagating through the waveguide structure, such that the first optical wave transitions due to the changed wavevector of the first optical wave from the first optical mode to a second optical mode as it propagates through the tapered first section towards a second end, distinct from the first end, of the waveguide structure.