Experimental study of acoustical memory in lithium niobate.
In this paper, the acoustical memory effect is studied from 2.5 to 10 MHz. This acoustical memory effect has been observed in both columnar and cubic samples. The observed phenomenon of amplitude hysteresis of the acoustical memory signal suggests nonclassical nonlinear properties, caused by the structural inhomogeneity and inevitable flaws in LiNbO3 . Experimental results also show that the amplitude of the acoustical memory signal is enhanced by increasing the temperature at these frequencies. The shape of the memory signal changes greatly if the driving voltage is sufficiently high or each burst contains enough cycles; second and even third parts of the acoustical memory signals may appear. Amplitude hysteresis of the fundamental and second harmonic of the direct wave can also be found. Some experimental results are qualitatively explained in this paper.
Zhou
Dao
D
Key Laboratory of Modern Acoustics, Ministry of Education, Institute of Acoustics, Nanjing University, Nanjing 210093, People's Republic of China.
Liu
Xiaozhou
X
Gong
Xiufen
X