Large single crystal growth, transport property and spectroscopic characterizations of three-dimensional Dirac semimetal Cd3As2

Abstract

The three dimensional (3D) Dirac semimetal is a new quantum state of matter that has attracted much attention recently in physics and material science. Here, we report on the growth of large plate-like single crystals of Cd3As2 in two major orientations by a self-selecting vapor growth (SSVG) method, and the optimum growth conditions have been experimentally determined. The crystalline imperfections and electrical properties of the crystals were examined with transmission electron microscopy (TEM), scanning tunneling microscopy (STM), and transport property measurements. This SSVG method makes it possible to control the as-grown crystal compositions with excess Cd or As leading to mobilities near 5–105 cm2V−1s−1. Zn-doping can effectively reduce the carrier density to reach the maximum residual resistivity ratio (RRRρ300K/ρ5K) of 7.6. A vacuum-cleaved single crystal has been investigated using angle-resolved photoemission spectroscopy (ARPES) to reveal a single Dirac cone near the center of the surface Brillouin zone with a binding energy of approximately 200 meV.

3D Dirac semimetal Cd3As2 : A review of material properties

“…4. Schematic cross-sectional side view of an alumina furnace used for self-selecting vapor growth of a Cd3As2 single crystal [39]. The positions of the ampoule in which transport takes place and the temperature profile of the furnace for Cd3As2 growth are shown.…”

“…Most recently, the fast developing field of Cd 3 As 2 has been largely dominated by experiments [6, 24-27, 31, 46] performed on samples prepared by either growth from a Cd-rich melt [20], or self-selecting vapor growth (SSVG) [39], which are below described in greater detail. With Cd-rich melt, Cd 3 As 2 is synthesized from a Cd-rich mixture of elements sealed in an evacuated quartz ampoule, heated to 825 • C, and kept there for 48 hours.…”

“…The SSVG method comprises several steps [39]. In the first, the compound is synthesized from a stoichiometric mixture of elements in an evacuated sealed ampoule, and heated for 4 hours 50 • C above the Cd 3 As 2 melting point.…”

Effects of Cd vacancies and unconventional spin dynamics in the Dirac semimetal Cd3As2

“…Unconventional phenomena and physical properties including exotic electrical and thermal conductivity, high-temperature linear quantum magnetoresistance and oscillating quantum spin Hall effects have been detected by angle resolved photoemission spectroscopy (ARPES) and magneto-transport techniques [2][3][4][5][6][7][8][9][10][11] .…”

“…Cadmium arsenide (Cd3As2) is a " ## % & chemically stable n-type semiconductor with high carrier mobility, which makes it a candidate for device applications [1][2][3][4][5][6][7][8] . Cd3As2 was predicted theoretically by Wang et al 2 to be a Dirac semimetal (DSM).…”