Professor Mingzhong Wu gave a plenary talk on topological insulator/magnetic insulator hetero-structures in the XVIII Brazil MRS Meeting which were held in Balneario Camboriu, Brazil on September 22-26, 2019. The Brazil MRS Meetings are organized by the Brazilian Materials Research Society (MRS) and are the largest conferences on materials in Brazil. Over 1800 people attended the XVIII Brazil MRS Meeting. https://www.sbpmat.org.br/18encontro/