Intermetallic bismuth-based compounds
have attracted great interest
as promising candidates for novel topological superconductivity. Among
them, CaBi2 is a newly discovered member for which the
atomic structure and electronic properties have never been systematically
explored. Using low-temperature scanning tunneling microscopy/spectroscopy
(STM/S), we systematically characterized the atomic structure and
electronic properties of CaBi2(010) thin films grown by
molecular beam epitaxy (MBE) and found that their growth follows a
Stranski-Krastanov mode. A nonreconstructed IBi layer and
a (1 × 2) reconstructed IICa layer were found to be
the most common surfaces. Nonreconstructed IIIBi and VCa layers were further exposed with reduced bismuth growth
flux. All of these constituent layers exhibit unique features in the
STS spectra, indicating that unique electronic properties exist in
each specific constituent layer. Our findings provide for deeper understanding
of the physical properties of this compound and suggest further studies
of the two-dimensional (2D) layered materials family.