Temperature–field phase diagram of extreme magnetoresistance

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 113; no. 25; pp. E3475 - E3481
• Main Authors: Tafti, Fazel Fallah, Gibson, Quinn, Kushwaha, Satya, Krizan, Jason W., Haldolaarachchige, Neel, Cava, Robert Joseph
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 21.06.2016
• Series: PNAS Plus
• Subjects: Band structure; Comparative analysis; Comparative studies; Crystal structure; Lanthanum; Magnetic fields; Physical Sciences; PNAS Plus; Symmetry; topological semimetal; extreme magnetoresistance; orbital texture
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1607319113

The recent discovery of extreme magnetoresistance (XMR) in LaSb introduced lanthanum monopnictides as a new platform to study this effect in the absence of broken inversion symmetry or protected linear band crossing. In this work, we report XMR in LaBi. Through a comparative study of magnetotransport effects in LaBi and LaSb, we construct a temperature–field phase diagram with triangular shape that illustrates how a magnetic field tunes the electronic behavior in these materials. We show that the triangular phase diagram can be generalized to other topological semimetals with different crystal structures and different chemical compositions. By comparing our experimental results to band structure calculations, we suggest that XMR in LaBi and LaSb originates from a combination of compensated electron–hole pockets and a particular orbital texture on the electron pocket. Such orbital texture is likely to be a generic feature of various topological semimetals, giving rise to their small residual resistivity at zero field and subject to strong scattering induced by a magnetic field.