Pressure-induced superconductivity in magnetic topological insulator candidate MnSb4Te7

The magnetic van der Waals crystals ${(\mathrm{Mn}\phantom{\rule{0.16em}{0ex}}{X}_{2}{\mathrm{Te}}_{4})}_{m}{({X}_{2}{\mathrm{Te}}_{3})}_{n}$ $(X=\mathrm{Sb},\phantom{\rule{0.28em}{0ex}}\mathrm{Bi})$ have drawn significant attention due to their rich topological properties and tenability by external magnetic field. In this letter, we report on the discovery of superconductivity in magnetic topological insulator candidate ${\mathrm{MnSb}}_{4}{\mathrm{Te}}_{7}$ ($m=1$, $n=1$) via the application of high pressure. The antiferromagnetic ordering is robust to pressure until 8 GPa and then fully suppressed. The carrier type converts from hole to electron accompanied with structural phase transition at $\ensuremath{\sim}16\phantom{\rule{0.28em}{0ex}}\mathrm{GPa}$. Superconductivity emerges near the critical pressure 30 GPa where ${\mathrm{MnSb}}_{4}{\mathrm{Te}}_{7}$ converts to phase III. Interestingly, ${\mathrm{MnSb}}_{4}{\mathrm{Te}}_{7}$ shows a domelike phase diagram with a maximum ${T}_{\mathrm{c}}$ of 2.2 K at 50.7 GPa.