Tunable and broadband microwave frequency combs based on a semiconductor laser with incoherent optical feedback
*
Zhao Mao-Rong
a)
, Wu Zheng-Mao
a)
, Deng Tao
a)
, Zhou Zhen-Li
a)
, Xia Guang-Qiong
a),
b)†
Δ f versus the feedback delay time τ under κ
f
= 0.2, where (a) I = 1.5 I
th
, (b) I = 2 I
th
, (c) I = 2.5 I
th
, and (d) I = 3 I
th
.