Large Magnetoresistance and Nontrivial Berry Phase in Nb₃Sb Crystals with A15 Structure

Abstract

Compounds with the A15 structure have attracted extensive attention due to their superconductivity and nontrivial topological band structures. We have successfully grown Nb3Sb single crystals with the A15 structure and systematically measured the longitudinal resistivity, Hall resistivity and quantum oscillations in magnetization. Similar to other topological trivial/nontrivial semimetals, Nb3Sb exhibits large magnetoresistance (MR) at low temperatures (717%, 2 K and 9 T), unsaturating quadratic field dependence of MR and up-turn behavior in ρxx (T) curves under magnetic field, which is considered to result from a perfect hole-electron compensation, as evidenced by the Hall resistivity measurements. The nonzero Berry phase obtained from the de-Hass van Alphen (dHvA) oscillations demonstrates that Nb3Sb is topologically nontrivial. These results indicate that Nb3Sb superconductor is also a semimetal with large MR and nontrivial Berry phase. This indicates that Nb3Sb may be another platform to search for the Majorana zero-energy mode.

Intrinsic V vacancy and large magnetoresistance in V1 — δ Sb2 single crystal

“…At T = 1.8 K, V 1−δ Sb 2 single crystal exhibits a large MR of 447% at B = 12 T. With the increase of temperature, MR is suppressed significantly but still remain about 18.2% at 300 K. The classical carrier compensation mechanism was used to explain the large and non-saturating quadratic MR, such as that of in WP 2 [33] and Nb 3 Sb. [34] Based on the band structure calculation in Fig. 5, although we observed the electron and hole pockets from Γ to X point, such a mechanism seemed to be invalid because the field dependence of MR in V 1−δ Sb 2 single crystal was of significant deviation from quadratic behavior.…”

Negative magnetoresistance in the antiferromagnetic semimetal V1/3TaS2

“…To parameterize the Hall data, we analyze the longitudinal and Hall resistivity using a two-carrier model, as we discuss for other semimetals. [24][25][26][27][28][29] In this model, the conductivity tensor in its complex representation is given as [30] σ = e n e µ e 1 + iµ e µ 0 H…”