Superconductivity of the Linear Trichalcogenide NbSe3under Pressure

We show that the linear compound Nb${\mathrm{Se}}_3$ becomes superconducting under pressure. We have measured the initial slope of the magnetization of Nb${\mathrm{Se}}_3$ as a function of pressure down to temperatures as low as 50 mK. A very small pressure is necessary in order for the superconductivity to occur. $T_c$ is strongly pressure dependent. We find that the initial slope $\frac{d{T}_c}{\mathrm{dP}}=0.6\mathrm{}$ K/bar. We attribute this huge variation of $T_c$ to changes in the band structure induced by pressure.