Design of cost-effective environment-responsive nanoacoustic devices based on mesoporous thin films

Abstract

Gigahertz acoustic resonators have the potential to advance data processing and quantum communication. However, they are expensive and lack responsiveness to external stimuli, limiting their use in sensing applications. In contrast, low-cost nanoscale mesoporous materials, known for their high surface-to-volume ratio, have shown promise in various applications. We recently demonstrated that mesoporous silicon dioxide (SiO2) and titanium dioxide (TiO2) thin layers can support coherent acoustic modes in the 5 to 100 GHz range. In this study, we propose a new method for designing tunable acoustic resonators using mesoporous thin films on acoustic distributed Bragg reflectors. By simulating the infiltration of the pores with water, we show that the material’s properties could be altered and achieve tunability in the acoustic resonances. We present four device designs and use simulations to predict resonators with Q-factors up to 1500. We also observe that the resonant frequency and intensity show a linear response to water infiltrated in the mesopores, with a tunability of up to 60%. Our platform offers a unique opportunity to design cost-effective nanoacoustic sensing and reconfigurable optoacoustic nanodevices.

Mesoporous-based responsive acoustic resonators operating in the GHz range

“…Additionally, positioning the mesoporous thin film as the outermost layer of the structure facilitates easier infiltration of liquids and vapors. 15 Our findings highlight the practical utility of this device for realizing tunable and reconfigurable optophononic devices within the GHz range. As a perspective, we aim to investigate the resonance dependency on liquid infiltration through pump-probe experiments conducted at varying relative humidity levels.…”

“…This may involve investigating the devices at different humidity conditions, exploring alternative pore size distributions, optimizing fabrication processes, and exploring novel integration schemes with complementary materials, geometries, and components. 7,15,23,24…”

“…In particular, mesoporous SiO 2 and TiO 2 have emerged as viable candidates due to their ability to support acoustic resonances in the 5-100 GHz frequency range while also exhibiting susceptibility to environmental stimuli, such as liquid and vapor infiltration. [13][14][15][16] Leveraging these properties, we propose a novel design of open-cavity acoustic resonators based on mesoporous SiO 2 thin films (MTFs), engineered to be responsive to changes in environmental humidity.…”

Design of responsive mesoporous-based open-cavity acoustic resonators operating in the GHz range

“…1 Tens-of-gigahertz nanoacoustic resonators are usually based on multilayered distributed Bragg reflectors (DBRs). [2][3][4][5][6][7][8][9][10] The lack of tunability of such resonators can be the bottleneck for further advancements, and therefore, developing strategies for dynamical tuning of acoustic resonators, a nearly unexplored field, 1,11,12 is of utmost importance in the nanophononics domain. A potential candidate for active tunable acoustic resonator are the mesoporous thin films (MTFs), with pores at the nanoscale.…”

“…[18][19][20] By designing an acoustic resonator with MTFs as the active elements, the acoustic resonance shifts in frequency and amplitude under liquid infiltration. 11,12 Here, we theoretically propose the design of acoustic resonators based on such structures, and demonstrate two case studies.…”