Performance Analysis On Phonon Lasers Of Phononic Grating Modulation

Phonon laser is the first device capable of transmitting sound waves in the terahertzfrequency range, which produces a continuous phonon beam with nanometer wavelengths.Terahertz frequency sound waves can be used to probe nanoscale materials, the phonon beamgenerated by the phonon laser will also be a good use in computer calculation, medical imagingand security checks.In this paper, a method to improve the phonon laser performance was proposed, and a phonicgrating was designed to improve the linewidth. First of all, we compared the effects of differentmedia thickness to the defect mode. Then the effects of different dielectric materials and impuritymaterial to the defect mode were discussed. Simulating results show that the phonic gratingused an alternating structure composed by epoxy and water was best, and the filteringperformance with magnesium impurity incorporated was the most outstanding.The phonic grating was connected to the Resonator Phonon Laser. Phononic band gap and defectmode in the phonic grating are analyzed by Transfer Matrix Method. Simulating results show thatthe diversification between the maximum transmission rate of defect mode and the impuritythickness acts as a cosine curve with the stability of the thickness of all other layers. With theincrease of the impurity absorption coefficient, the maximum transmission rate decreases rapidly.The linewidth of the phonon laser was1.94Hz. While the incident laser had an angle of60,the linewidth of the phonon laser was1.97Hz. We also simulated the shifting feature in phononicband gap which does not exist in photonic crystals. This phonic grating has good modulationeffects for the phonon laser, which will be widely used in phonon laser system in the future.