講演情報
[20a-C501-7]Epitaxial growth and characterization of superconductor Al / ferromagnetic semiconductor (In,Fe)As heterostructures on InP substrates
〇Hirotaka Hara1, Keita Ishihara1, Le Duc Anh1,2,3, Masaaki Tanaka1,3 (1.EEIS, Tokyo Univ., 2.PRESTO, JST, 3.CSRN, Tokyo Univ.)
キーワード：
heterostructure、ferromagnetic semiconductor
In this work, we have successfully grown epitaxial SC (Al) / FMS (In,Fe)As heterostructures on InP (001) substrates, by molecular beam epitaxy. The Al/(In,Fe)As bilayers were grown on three types of (In1-x,Alx)As buffer layers with x = 0.1, 0.15, 0.19, and thus experience different in-plane compressive strains (-0.65%, -0.81%, -0.97%, respectively). The (In,Fe)As films exhibit ferromagnetism (Curie temperature TC are 40 K, 45K, 60 K, respectively), which is confirmed by magnetic circular dichroism (MCD), but become insulating at low temperature. These results indicates that strain can affect the ferromagnetism and transport in (In,Fe)As. On the other hand, the Al layers are successfully grown in the [111] direction, as revealed by transmission electron microscopy (TEM), and become superconducting around 1.2 K. These Al/(In,Fe)As heterostructures are good material candidates for investigating superconductor spintronics.