Growth and terahertz conductivity of epitaxial Mn3Sn thin films

The magnetic Weyl semimetal has Berry curvature in the momentum space near Fermi level, leading to large anomalous Hall effect, anomalous Nernst effect and magneto-optical effect in such materials. It is still challenging to grow high quality epitaxial Mn 3 Sn thin films with transport and optical properties comparable to their single crystal counterparts. Meanwhile, the anisotropic conductivity has not been studied on Mn 3 Sn in THz frequencies. Here, we report the structure, magneto-optical and transport properties of epitaxial Mn 3+x Sn 1-x thin films fabricated by pulsed laser deposition (PLD). Highly oriented Mn 3+x Sn 1-x (0001) and $\left({11\bar 20}\right)$ epitaxial films are successfully growth on single crystalline Al 2 O 3 and MgO substrates. The terahertz conductivity in Mn 3 Sn films is investigated by polarization-resolved spectroscopy. Our work demonstrates strong terahertz conductivity in epitaxial Mn 3+x Sn 1-x films, paving the way for future optical and spintronic device applications.