Spectrally wide acoustic frequency combs generated using oscillations of polydisperse gas bubble clusters in liquids

Acoustic, Phononic, Brillouin Light Scattering and Faraday Wave-Based Frequency Combs: Physical Foundations and Applications

“…As seen from Figure 14 b, the shape of spectral peaks is slightly irregular and it could be argued that this artefact is associated with a translational motion of oscillating bubbles in the incident ultrasound field. Therefore, the question of long-term stability of AFC signals arises, which was comprehensively addressed in [ 22 ].…”

“…In [ 22 ], an alternative strategy for broadening spectra of AFCs generated using gas bubble oscillations was suggested using polydisperse clusters consisting of mm-sized bubbles with equilibrium radii , where is the equilibrium radius of the largest bubble in the cluster and is the total number of bubbles. Although clusters with other bubble size distributions could also be used in the proposed approach, it was shown that this specific ratio of equilibrium radii enables generating AFCs with a quasi-continuum of equally spaced peaks.…”

“…Although clusters with other bubble size distributions could also be used in the proposed approach, it was shown that this specific ratio of equilibrium radii enables generating AFCs with a quasi-continuum of equally spaced peaks. Similarly to the experiment [ 21 ], in the analysis in [ 22 ] low-pressure ultrasound waves (up to 10 kPa) were considered and a numerical model of dynamics of multibubble clusters with translational motion developed in [ 133 , 144 , 152 ] was employed.…”

“…In Section 5 , we review FCs obtained using the Brillouin light scattering effect [ 16 , 17 , 18 ], and we also demonstrate the possibility of increasing the amplitude of spectral peaks in the comb spectra by means of plasmonic resonant effects supported by metal nanostructures [ 19 , 20 ]. The discussion of the novel approaches to the generation of AFCs continues in Section 6 and Section 7 , where we review the recent advances in the fields of AFC generated using oscillations of gas bubbles in liquids [ 21 , 22 ] and vibrations of liquid drops [ 23 , 24 ], respectively. There, the reader will find a detailed analysis of both experimental and theoretical results [ 22 ] including those obtained using drops of room-temperature liquid metal alloys that have recently attracted significant attention in the fields of material science, electronics and optics [ 25 , 26 , 27 , 28 ].…”

“…The discussion of the novel approaches to the generation of AFCs continues in Section 6 and Section 7 , where we review the recent advances in the fields of AFC generated using oscillations of gas bubbles in liquids [ 21 , 22 ] and vibrations of liquid drops [ 23 , 24 ], respectively. There, the reader will find a detailed analysis of both experimental and theoretical results [ 22 ] including those obtained using drops of room-temperature liquid metal alloys that have recently attracted significant attention in the fields of material science, electronics and optics [ 25 , 26 , 27 , 28 ]. The main discussion is concluded by an analysis of challenges faced by developers of the AFC technology and a discussion of the potential directions for future research.…”