  Non-collinear antiferromagnet Weyl semimetal $Mn_3Sn$ have attracted great
research interest recently. Although large anomalous Hall effect, anomalous
Nernst effect and magneto-optical effect have been observed in $Mn_3Sn$, most
studies are based on single crystals. So far, it is still challenging to grow
high quality epitaxial $Mn_3Sn$ thin films with transport and optical
properties comparable to their single crystal counterparts. Here, we report the
structure, magneto-optical and transport properties of epitaxial $Mn_3Sn$ thin
films fabricated by pulsed laser deposition (PLD). Highly oriented
$Mn_{3+x}Sn_{1-x}$ (0001) and (11$\bar2$0) epitaxial films are successfully
growth on single crystalline $Al_2O_3$ and MgO substrates. Large anomalous Hall
effect (AHE) up to $\left| \Delta R_H\right|$=3.02 $\mu\Omega\cdot cm$, and
longitudinal magneto-optical Kerr effect (LMOKE) with $\theta_K$ = 38.1 mdeg at
633 nm wavelength are measured at 300 K temperature, which are comparable to
$Mn_3Sn$ single crystals. Our work demonstrates that high quality $Mn_3Sn$
epitaxial thin films can be fabricated by PLD, paving the way for future device
applications.
