  Dissipative Kerr-microresonator soliton combs (hereafter called soliton
combs) has been rapidly progressing as compact frequency combs. Comb mode
scanning of the soliton combs with a large range and fast speed is of paramount
importance for applications such as LiDAR and spectroscopy, requiring large and
rapid frequency scanning of a pump continuous-wave (CW) laser as well as
resonance frequency of a microresonator. Here, we demonstrate the generation of
a soliton comb by a distributed feedback (DFB) laser toward the comb mode
scanning with a large range and fast speed. Compared with conventional pump CW
lasers (i.e. external cavity diode lasers: ECDLs), DFB lasers can be
frequency-scanned more largely and rapidly without mode-hopping. In addition,
because of the fast scan speed of the DFB laser, a single soliton comb is
generated simply by controlling the injection current of the DFB laser, greatly
simplifying the system without having any additional optical modulators such as
a carrier-suppressed single-sideband modulator (CS-SSB modulator),
acousto-optic modulator (AOM), and auxiliary CW laser.
