Enhancement effect of cumulative second-harmonic generation by closed propagation feature of circumferential guided waves
Gao Guang-Jian1, Deng Ming-Xi2, †, Hu Ning2, Xiang Yan-Xun3, ‡
       

Normalized relative nonlinearity parameter of primary CGW versus θ: (a) βR(n=1) and βR(n=2) , and (b) Δ βR.