Quantum Transport Evidence for the Three-Dimensional Dirac Semimetal Phase inCd3As2

Abstract

We report the quantum transport properties of Cd₃As₂ single crystals in a magnetic field. A large linear quantum magnetoresistance is observed near room temperature. With decreasing temperature, the Shubnikov-de Haas oscillations appear in both the longitudinal resistance R(xx) and the transverse Hall resistance R(xy). From the strong oscillatory component ΔR(xx), a linear dependence of the Landau index n on 1/B is obtained, and it gives an n-axis intercept between 1/2 and 5/8. This clearly reveals a nontrivial π Berry's phase, which is a distinguished feature of Dirac fermions. Our quantum transport results provide bulk evidence for the existence of a three-dimensional Dirac semimetal phase in Cd₃As₂.

Nearly massless Dirac fermions and strong Zeeman splitting in the nodal-line semimetal ZrSiS probed by de Haas–van Alphen quantum oscillations

“…From these fits we have extracted high carrier density, 3.64×10 20 and 3.59×10 20 cm -3 , for electron and hole bands respectively, which are significantly higher than those of other Dirac systems such as Cd 3 As 2 (~10 18 cm -3 [15,[57][58][59]66]), Na 3 Bi (~10 17 cm -3 [79]), topological insulators (~10 10-12 cm -3 [69]), as well as graphene (10 10-12 cm -3 [80][81]). Furthermore, from the two-band model fitting we also estimated a transport mobility of ~13,700 cm 2 /Vs for holes and 12,300 cm 2 /Vs for electrons.…”

Pressure-induced superconductivity in the three-dimensional topological Dirac semimetal Cd3As2

“…On the basis of quantum transport measurement, a non-trivial π Berry's phase is obtained, which provides bulk evidence for the existence of 3D Dirac semimetal phase in Cd 3 As 2 . 28,29 By symmetry breaking, this 3D Dirac semimetal may be driven to a topological insulator or Weyl semimetal. 23 More interestingly, it was predicted that topological superconductivity may be achieved in Cd 3 As 2 by carrier doping, 23 but this has not been realised so far.…”

“…[18][19][20][21][22][23][24][25][26][27][28][29] As a 3D analogue to graphene, the Fermi surface of the 3D Dirac semimetal only consists of 3D Dirac points with linear energy dispersion in any momentum direction. 19,23 The exotic Fermi surface of Na 3 Bi and Cd 3 As 2 was confirmed by the angle-resolved photoemission spectroscopy experiments.…”

Topological semimetals with helicoid surface states

“…The nontrivial topology gives rise to anomalous bulk properties of topological semimetals such as the chiral anomaly [3][4][5]. Several classes of topological semimetals have been theoretically proposed so far, including Weyl, [2,[6][7][8][9][10][11][12][13], Dirac [14][15][16][17] and nodal line semimetals [7,[17][18][19][20][21][22][23][24][25][26][27][28][29][30], some among which have been experimentally observed [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47].Surface states of topological semimetals have attracted much attention. On the surface of a Weyl semimetal, the Fermi surface consists of open ar...…”