Ultrasonic Gas Sensing by Two-Dimensional Surface Phononic Crystal Ring Resonators

ÇİÇEK A., Trak D., ARSLAN Y., KÖRÖZLÜ N., KAYA O. A., ULUĞ B.

ACS SENSORS, vol.4, no.7, pp.1761-1765, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 4 Issue: 7
  • Publication Date: 2019
  • Doi Number: 10.1021/acssensors.9b00865
  • Journal Name: ACS SENSORS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1761-1765
  • Keywords: ultrasonic gas sensors, Helmholtz cavity, phononic crystal, ring resonator, finite-element method, FLUORESCENT CHEMOSENSOR, SENSOR SYSTEM, METHANE, CO2, SOUND
  • Akdeniz University Affiliated: Yes

Abstract

An acoustic ring resonator employing a two-dimensional surface phononic crystal is proposed for high-sensitivity detection in binary gas mixtures. Band analyses and frequency-domain simulations via the finite-element method reveal that a single band for spoof surface acoustic waves appears at ultrasonic frequencies around 58 kHz where modification of its dispersion due to varying gas composition results in a linear shift of the resonance frequency. The shift rate is -17.3 and 8.8 mHz/ppm for CO2 and CH4, respectively. The linear shift of resonance frequency is experimentally validated. In addition, the ring resonator can also be employed to track acoustic intensity variation with gas concentration, where exponentially decaying intensity for low concentrations leverages high-sensitivity operation.