###### Abstract  
Love wave sensors have attracted significant interest due to their high sensitivity and low attenuation. Love mode acoustic dispersion relation, highest normalized mass sensitivity, optimum normalized waveguide layer thickness, and temperature coefficients of frequency (TCF) were theoretically studied for the carbon fiber epoxy composites (CFEC)/Mn:0.24 PIN-0.46 PMN-0.30 PT structure sensor. The highest normalized mass sensitivity exhibits a decreasing trend as the temperature increases from 25 \({}^{\circ}\)C to 55 \({}^{\circ}\)C. TCF can be improved by increasing the normalized layer thickness (\(\ll\)/\(\lambda\)); however, the temperature dependence of normalized mass sensitivity decreases. For the carbon fibers (CFs) in the CFEC waveguide along the propagation direction of Love wave, the device has a relatively small TCF of \(-10.92\) ppm/\({}^{\circ}\)C at \(\ll\)/\(\lambda\)= 0.4001, where the normalized mass sensitivity is approximately 1.5 times that of a typical fused quartz/ST-quartz configuration device. The theoretical results imply that good temperature stability and high measurement precision were obtained from the device in the system CFEC/Mn:0.24 PIN-0.46 PMN-0.30 PT with the CFs in the CFEC along the propagation direction of Love wave (\(x\)-axis). The ideal waveguide material requires a small elastic constant \(c_{44}\); however, the ideal piezoelectric substrate requires large elastic constants \(c_{44}^{E}\) and \(c_{66}^{E}\). p ezoelectric single crystal; Love wave sensor; temperature stability; acoustic properties 0.24 PIN-0. layer can result in a change in frequency [4]. At a certain temperature, by measuring the frequency shift, the mass of the load can be obtained accurately when the mass sensitivity is provided. In general, the ambient temperature is not constant; therefore, it is very important to determine the relationship between mass sensitivity and temperature to ensure the measurement accuracy of the device. To eliminate the influence of ambient temperature, temperature-compensated Love wave sensors have been studied. The temperature coefficient of frequency (TCF) is zero in theory for a SiO\({}_{2}\)/LiTaO\({}_{3}\) structure device for a normalized layer thickness of 0.255; however, the sensitivity to mechanical surface perturbations of the structure is only approximately 50% of that of the traditional SiO\({}_{2}\)/quartz sensor [5]. Although the TCF can attain a very small value of +0.75 ppm/K for the polymethyl methacrylate (PMMA)/ST-quartz structure device for a normalized guiding layer thickness of 0.0381, the temperature compensation effect is weakened because of aging as the PMMA is a polymer and ages easily [6]. The temperature coefficient of delay (TCD) can reach zero and the mass sensitivity can be improved by adding a SiO\({}_{2}\) buffer layer in the ZnO/Si structure device; however, the electromechanical coupling coefficient in the configuration is still very low [7]. For a device with multi-guide layers, a very small TCF of +2.16 ppm/\({}^{\circ}\)C was obtained with the SU-8/SiO\({}_{2}\)/ST-90\({}^{\circ}\)X quartz configuration, but the insertion loss increased with temperature [8]. Note that SU-8 is a cross-linked photoresist with a glass transition temperature of over 200 \({}^{\circ}\)C [9]. For practical Love wave devices, while attaining zero TCF, it is also necessary to maintain high sensitivity and high electromechanical coupling [10]. A dual-channel configuration of the delay-line oscillators was used to compensate for temperature drift [11; 12; 13; 14]. The temperature effects can be compensated to a considerable degree by using dual-channel devices, but it is nevertheless of importance to minimize the temperature coefficient of oscillation frequency for the devices [15]. Choosing suitable waveguide materials will help improve the performance of the device. A polymer waveguide, such as PMMA and SU-8, exhibits the characteristics of low horizontal shear (SH) wave velocity and low density, which improve the performance.