  Recent band structure calculations have suggested the potential for band
tuning in a chiral semiconductor, Ag$_3$AuTe$_2$, to zero upon application of
negative strain. In this study, we report on the synthesis of polycrystalline
Ag$_3$AuTe$_2$ and investigate its transport, optical properties, and pressure
compatibility. Transport measurements reveal the semiconducting behavior of
Ag$_3$AuTe$_2$ with high resistivity and an activation energy $E_a$ of 0.2 eV.
The optical band gap determined by diffuse reflectance measurements is about
three times wider than the experimental $E_a$. Despite the difference, both
experimental gaps fall within the range of predicted band gaps by our
first-principles DFT calculations employing the PBE and mBJ methods.
Furthermore, our DFT simulations predict a progressive narrowing of the band
gap under compressive strain, with a full closure expected at a strain of -4%
relative to the lattice parameter. To evaluate the feasibility of gap
tunability at such substantial strain, the high-pressure behavior of
Ag$_3$AuTe$_2$ was investigated by $in$ $situ$ high-pressure X-ray diffraction
up to 47 GPa. Mechanical compression beyond 4% resulted in a pressure-induced
structural transformation, indicating the possibilities of substantial gap
modulation under extreme compression conditions.
