Multiple fields coupled elastic flexural waves in the thermoelastic semiconductor microbeam with consideration of small scale effects

The possible elastic flexural waves in a thermoelastic semiconduction micro-beam are studied in present work. The coupling effects of the carrier field, temperature field and the elastic displacement field are considered. The nonlocal strain gradient elasticity and the non-Fourier heat conduction are incorporated into a generalized thermoelastic model to take the small scale effects into account. Besides, the fraction derivative is introduced to replace the integer order derivative to get a more flexible and enriched model with the multiple physical fields coupled. It is found that there are totally five possible coupled elastic waves. These coupled elastic waves will reduce to the plasma wave, the thermal wave, one propagating elastic flexural wave and two standing elastic flexural waves when the coupling effects among the three kinds of physical fields are ignored. The dispersion and attenuation characteristics and their coupling modes of the five possible flexural elastic waves are compared. The influences of the nonlocal parameter, the strain gradient parameter, thermal relaxation time and the fraction order parameters are discussed based on the numerical results.

Automated summary

This study investigates the possible coupled elastic waves in a thermoelastic semiconduction micro-beam, considering the coupling effects of the carrier field, temperature field, and elastic displacement field. By incorporating nonlocal strain gradient elasticity, non-Fourier heat conduction, and fraction derivative into the model, a more flexible and enriched model with multiple physical fields coupled is obtained. The study reveals the existence of five possible coupled elastic waves, with comparisons made on the dispersion and attenuation characteristics and their coupling modes. Analysis on the influences of nonlocal parameter, strain gradient parameter, thermal relaxation time, and fraction order parameters are discussed based on numerical results.