Mixed conductivity analysis of single crystals of α‴-(Cd1−x Znx)3As2 (x = 0.45)

Abstract

We study the conductivity and magnetoresistance of the α‴ phase solid solution of (Cd1−xZnx)3As2 (x = 0.45). Single crystals of (Cd1−xZnx)3As2 are obtained by the modified Bridgman method. The space group and tetragonal lattice parameters of single crystals are found to be I41/amd and a = b = 8.56(5) Å, c = 24.16(6) Å. The temperature dependence of the conductivity and magnetoresistance is studied in the temperature range of 1.6–320 K and in the presence of a transverse magnetic field from 0 to 10 T. Mixed conductivity is analyzed using Hall resistivity data and standard quantitative mobility spectrum analysis. The concentration and mobility of holes are determined at different temperatures. The presence of two types of holes with different mobilities is demonstrated in the temperature range of 1.6–19 K, while with increasing temperature, just one type of charge carrier is observed in the mobility spectrum.

Material descriptors for thermoelectric performance of narrow-gap semiconductors and semimetals

“…72 Several other polymorphs of Zn 3 As 2 are known, including the room-temperature a phase (I4 1 /acd), 73 the high-temperature a 0 phase (P4 2 /nbc), 74,75 another hightemperature b phase (Fm% 3m), 76 and the high-temperature, high-pressure a 00 phase (P4 2 /nmc). 77,78 The TE properties of Cd 3 As 2 -Zn 3 As 2 alloys have been studied, [79][80][81][82] but the transport properties of the Ia% 3 phase has not been measured. There are three conduction bands that are close in energy and located at the Brillouin zone edges (Fig.…”

Material Descriptors to Predict Thermoelectric Performance of Narrow-gap Semiconductors and Semimetals

“…68 Several other polymorphs of Zn 3 As 2 are known, including the room-temperature ↵ phase (I4 1 /acd), 69 the high-temperature ↵ 0 phase (P 4 2 /nbc), 70,71 another high-temperature phase (F m 3m), 72 and the high-temperature, high-pressure ↵ 00 phase (P 4 2 /nmc). 73,74 The TE properties of Cd 3 As 2 -Zn 3 As 2 alloys have been studied, [75][76][77][78] but the transport properties of the Ia 3 phase has not been measured. There are three conduction bands that are close in energy and located at the Brillouin zone edges (Figure 5d), yielding a valley degeneracy N V,CB of 3.…”