High-power beam steering with automatic Bragg matching in the double color-pumped Brillouin oscillator

The beam-steering capabilities of the double color-pumped oscillator by Brillouin four-wave mixing are analyzed and demonstrated for the first time to the author’s knowledge. The Brillouin reflection grating geometry is shown to give 3 orders of magnitude greater sensitivity of the beam deflection angle to the controllable parameters as compared with a transmission grating geometry. Theory predicts that at λ = 1.06 μm a 0.1% tuning of wavelength or birefringence with an ˜1° angle between the input beams will result in a deflection of ˜11° with ˜800 resolvable spots and an access time dictated by the decay of the electrostrictive grating (< 100 ns). The maximum deflection angle is not limited by the Bragg condition, which is always automatically satisfied in this device.