A Dual Love wave and Impedance-based Sensor: Response Enrichment

Love Wave acoustic sensors behavior in complex liquids. Multiparameter sensing using acoustic and electrical signals

“…From Fig. 3a , it can be observed that, in the presence of the liquid on the acoustic path, magnitude of the S 21 response of the LW device decreases, mainly due to the the mechanical parameters of the liquid sample, as the effect of electrical parameters are negligible in this case, as explained in [7], [8]. Also, a phase shift to the lower frequencies occurs due to the decrease of the LW phase velocity as in Fig.…”

“…LW sensor experiments with the "long chamber" PDMS chip provide an enriched response of the sensor, compared to the conventional method with the short chamber as demonstrated in [7], [8]. With liquid sample present on acoustic path as well as on the IDTs, indication about both the electrical and mechanical parameters of the complex liquid samples can be studied.…”

“…6b) clearly shows decrease in magnitude with increase in turbidity. As explained in [7], [8], S 11 response is highly sensitive to the electrical parameters of the liquid sample on the input IDT. Hence, these parameters can be investigated from S 11 response, mainly at frequencies lower than the acoustic resonance (50 MHz in our study) to facilitate the analysis with least influence of the acoustic phenomena.…”

“…Surface Acoustic Wave (SAW) sensors, especially Love Wave (LW) devices for sensing application in liquid media have already demonstrated their usefulness, as they provide a high sensitivity and reliable results for biochemical detection and liquid "mechanical" parameters estimation [1], [2], [3], [4], [5], [6]. Moreover, as LW sensors are based on acoustic transduction generated by piezoelectric phenomenon, both electrical and mechanical physics can be used for sensing purpose [7], [8]. Indeed, the knowledge of a large set of environmental physical data during the sample collection can improve the quality of the studies.…”

“…Indeed, the knowledge of a large set of environmental physical data during the sample collection can improve the quality of the studies. LW sensor allows an estimation of the change in input electrical impedance of the interdigitated transducers (IDTs) [7]. This change in electrical impedance is particularly due to the variations in the electrical parameters of the liquid samples contributed by the total dissolved solids (TDS) and total suspended solids (TSS) in the turbid solutions [9], [10], [7].…”