Intrinsic insulating transport characteristics in low-carrier density EuCd2As2 films

• DOI: 10.48550/arxiv.2401.02026
• Publication Date: 2024-01-01
• Authors: Shinichi Nishihaya; Ayano Nakamura; M. Ohno; M. Kriener; Yuto Watanabe; M. Kawasaki; Masaki Uchida
• Keywords: Weyl semimetal; Charge-carrier density; Lattice (music)

Searching for an ideal magnetic Weyl semimetal hosting only a single pair of points has been focal point systematic clarification its unique magnetotransport derived from the interplay between topology and magnetization. Among candidates, triangular-lattice antiferromagnet EuCd$_2$As$_2$ attracting special attention due to prediction phase in ferromagnetic state, however, transport properties low-carrier density samples have remained elusive. Here we report molecular beam epitaxy growth films, achieving low-hole range $10^{15}$-$10^{16}$ cm$^{-3}$ at low temperature. Transport measurements such films reveal insulating behavior with activation gap about 200 meV, which persists even field-induced state. Our work provides important experimental clue that is intrinsically insulating, contrary previous prediction.