Distorted weak anti-localization in pulsed laser-deposited Bi$_{\mathrm{2}}$Se$_{\mathrm{3}}$/La$_{\mathrm{0.70}}$Sr$_{\mathrm{0.30}}$MnO$_{\mathrm{3}}$ heterostructures

Topological insulator/ferromagnet (TI/FM) heterostructures with broken time reversal symmetry by interface-induced magnetism are potential platforms for the observation of novel quantum transport phenomena, magnetic monopoles and exotic quantum magneto-electric effects. One of the challenges encountered with TI/FM heterostructures is the low Curie temperatures of the ferromagnets studied so far which limits their potential for applications in spintronic devices at room temperature. In order to address this issue, we have grown Bi$_{\mathrm{2}}$Se$_{\mathrm{3}}$/La$_{\mathrm{0.70}}$Sr$_{\mathrm{0.30}}$MnO$_{\mathrm{3}}$\textbf{ }heterostructures by the method of pulsed laser deposition. La$_{\mathrm{0.70}}$Sr$_{\mathrm{0.30}}$MnO$_{\mathrm{3\thinspace }}$is a strong ferromagnetic material with T$_{\mathrm{c\thinspace }}$\textasciitilde 350 K and Bi$_{\mathrm{2}}$Se$_{\mathrm{3}}$ is the most studied topological insulator. XRD and phi scan results show that epitaxial thin films of Bi$_{\mathrm{2}}$Se$_{\mathrm{3\thinspace }}$are grown on the LSMO template. Strong in-plane magnetization is confirmed by magnetometry measurements of the Bi$_{\mathrm{2}}$Se$_{\mathrm{3}}$/LSMO heterostructure. Magneto-transport measurements show a distorted weak anti-localization effect with hysteretic behavior due to interface-induced ferromagnetism in the Bi$_{\mathrm{2}}$Se$_{\mathrm{3\thinspace }}$TI films. This work was supported, in part, by National Science Foundation ECCS-1306400.