Strong effects of uniaxial pressure and short-range correlations in Cr_{2}Ge_{2}Te_{6}

Abstract

Cr_{2}Ge_{2}Te_{6} is a quasi-two-dimensional semiconducting van der Waals ferromagnet down to the bilayer with great potential for technological applications. Engineering the critical temperature to achieve room-temperature applications is one of the critical next steps on this path. Here, we report high-resolution capacitance dilatometry studies on Cr_{2}Ge_{2}Te_{6} single crystals which directly prove significant magnetoelastic coupling and provide quantitative values of the large uniaxial pressure effects on long-range magnetic order (∂T_{C}/∂p_{c}=24.7 K/GPa and ∂T_{C}/∂p_{ab}=−15.6 K/GPa) derived from thermodynamic relations. Moderate in-plane strain is thus sufficient to strongly enhance ferromagnetism in Cr_{2}Ge_{2}Te_{6} up to room temperature. Moreover, unambiguous signs of short-range magnetic order up to 200 K are found.