Pressure tuning of the anomalous Hall effect in the chiral antiferromagnet Mn3Ge

We report on the pressure evolution of the giant anomalous Hall effect (AHE) in the chiral antiferromagnet ${\mathrm{Mn}}₃\mathrm{Ge}$. The AHE originating from the nonvanishing Berry curvature in ${\mathrm{Mn}}₃\mathrm{Ge}$ can be continuously tuned by application of hydrostatic pressure. At room temperature, the Hall signal changes sign as a function of pressure and vanishes completely at $p=1.53\phantom{\rule{0.28em}{0ex}}\mathrm{GPa}$. Even though the Hall conductivity changes sign upon increasing pressure, the room-temperature saturation value of $23\phantom{\rule{0.28em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ at 2.85 GPa is remarkably high and comparable to the saturation value at ambient pressure of about $40\phantom{\rule{0.28em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$. The change in the Hall conductivity can be directly linked to a gradual change of the size of the in-plane components of the Mn moments in the noncollinear triangular magnetic structure. Our findings, therefore, provide a route for tuning of the AHE in the chiral antiferromagnetic ${\mathrm{Mn}}₃\mathrm{Ge}$.