  Polaron is a composite quasiparticle derived from an excess carrier trapped
by local lattice distortion, and it has been studied extensively for decades
both theoretically and experimentally. However, atomic-scale creation and
manipulation of single-polarons in real space have still not been achieved so
far, which precludes the atomistic understanding of the properties of polarons
as well as their applications. Herein, using scanning tunneling microscopy, we
succeeded to create single polarons in a monolayer two-dimensional
semiconductor, CoCl2. Combined with first-principles calculations, two stable
polaron configurations, centered at on-top and hollow sites, respectively, have
been revealed. Remarkably, a series of manipulation progresses, from creation,
erasure to transition, can be accurately implemented on individual polarons.
Our results pave the way to understand the polaronic physics at atomic level,
and the easy control of single polarons in 2D semiconductor may open the door
to 2D polaronics including the data storage.
