Superconductivity was observed in the full-Heusler compound ${\mathrm{TiPd}}_2\mathrm{Ga}$ below 1.4 K. Polycrystalline samples of ${\mathrm{TiPd}}_2\mathrm{Ga}$ were prepared by the arc-melting method. ${\mathrm{TiPd}}_2\mathrm{Ga}$ adopts a centrosymmetric cubic structure with the space group Fm-$3m$. Electrical-resistivity and magnetic-susceptibility measurements reveal that ${\mathrm{TiPd}}_2\mathrm{Ga}$ is a type-II superconductor with a large Ginzburg-Landau parameter. The upper critical field ${\mu }_0{H}_{\mathrm{c}2}$ of $\sim 2.28$ T is slightly lower than the Bardeen-Cooper-Schrieffer Pauli limit (${\mu }_0{H}_{\mathrm{P}}=2.58$ T) in this three-dimensional superconductor with inversion symmetry, suggesting conventional superconducting states. Thermodynamic and transport data evidence the multigap weak-coupling BCS regime of ${\mathrm{TiPd}}_2\mathrm{Ga}$. In addition, we note that a charge density wave like transition lies at $\sim 90$ K. First-principles calculations indicate that the Pd-$4d$ and Ti-$3d$ orbits dominate the states at the Fermi level ($E_{\mathrm{F}}$), showing that different electronic components induce the multiband characters. The flat band topology and van Hove singularity near $E_{\mathrm{F}}$ contribute to the superconducting and charge instabilities in this system. The discovery of the first Ti-containing Heusler superconductor ${\mathrm{TiPd}}_2\mathrm{Ga}$ may benefit to make sense of the pairing mechanisms of Heusler-phase and other related intermetallic superconductors.

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• Superconductivity
• Heusler alloy
• Ab initio calculations
• Resistivity measurements
• Specific heat measurements
• Susceptibility measurements
• X-ray diffraction