We have studied Josephson junctions with barriers prepared from the Heusler compound ${\text{Cu}}_2\text{MnAl}$. In the as-prepared state the ${\text{Cu}}_2\text{MnAl}$ layers are nonferromagnetic and the critical Josephson current density $j_c$ decreases exponentially with the thickness of the Heusler layers $d_F$. On annealing the junctions at $240°\text{C}$ the Heusler layers develop ferromagnetic order and we observe a dependence $j_c\left(d_F\right)$ with $j_c$ strongly enhanced and weakly thickness dependent in the thickness range $7.0<d_F<10.6\text{nm}$. We interpret this feature as an indication of a triplet component in the superconducting pairing function generated by the specific magnetization profile inside thin ${\text{Cu}}_2\text{MnAl}$ layers.

• Received 21 July 2010

DOI:https://doi.org/10.1103/PhysRevB.82.060505