Monte Carlo simulations of acousto-optics with microbubbles

Acousto-optic (AO) signals can be very weak and the aim of this work was to investigate their amplification using microbubbles. The acoustic pressure radiated by the microbubbles produces refractive index changes in the surrounding medium, and this is proposed as an additional mechanism which modulates the phase of photons. The analytical form of this additional modulation is derived based on the Rayleigh-Plesset equation, which describes microbubble oscillations, in the case where the microbubble oscillations are linear under low applied ultrasound pressure. We show that microbubbles can increase the modulation depth of the AO signal using Monte Carlo simulations. The increase in modulation depth is dependent on the applied ultrasound frequency and the resonance frequency of the microbubbles.