Non-uniform carrier density in Cd${}_3$As${}_2$ evidenced by optical spectroscopy

Abstract

We report the detailed optical properties of Cd${}_3$As${}_2$ crystals in a wide parameter space: temperature, magnetic field, carrier concentration and crystal orientation. We investigate high-quality crystals synthesized by three different techniques. In all the studied samples, independently of how they were prepared and how they were treated before the optical experiments, our data indicate conspicuous fluctuations in the carrier density (up to 30%). These charge puddles have a characteristic scale of 100 $\mu$m, they become more pronounced at low temperatures, and possibly, they become enhanced by the presence of crystal twinning. The Drude response is characterized by very small scattering rates ($\sim 1$ meV) for as-grown samples. Mechanical treatment, such as cutting or polishing, influences the optical properties of single crystals, by increasing the Drude scattering rate and also modifying the high frequency optical response. Magneto-reflectivity and Kerr rotation are consistent with electron-like charge carriers and a spatially non-uniform carrier density.

arXiv commentAccepted in Physical Review B

References in corpus (18)

• Three Dimensional Dirac Semimetal and Quantum Transports in Cd3As2
• Ultrahigh mobility and giant magnetoresistance in the Dirac semimetal Cd${}_3$As${}_2$
• Observation of a topological 3D Dirac semimetal phase in high-mobility Cd3As2
• Experimental Realization of a Three-Dimensional Dirac Semimetal
• Landau Quantization and Quasiparticle Interference in the Three-Dimensional Dirac Semimetal Cd3As2
• Transport evidence for Fermi-arc mediated chirality transfer in the Dirac semimetal Cd${}_3$As${}_2$
• 3D massless Kane fermions observed in a zinc-blende crystal
• Cd3As2 is Centrosymmetric
• Three-dimensional Dirac fermions in quasicrystals as seen via optical conductivity
• Anisotropic Fermi Surface and Quantum Limit Transport in High Mobility 3D Dirac Semimetal Cd3As2
• Magneto-optical signature of massless Kane electrons in Cd3As2
• Interband optical conductivity of the [001]-oriented Dirac semimetal Cd3As2
• 3D Dirac cone carrier dynamics in Na3Bi and Cd3As2
• Transient reflectance of photoexcited Cd${}_3$As${}_2$
• Optical phonon dynamics and electronic fluctuations in the Dirac semimetal Cd3As2
• Probing the Fermi Surface of 3D Dirac Semimetal Cd${}_3$As${}_2$ through de Haas-van Alphen Technique
• Single crystal growth by the traveling solvent technique: A review
• Magneto-optical Kramers-Kronig analysis

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• Doping-induced topological transition and enhancement of thermopower in the Dirac-semimetal system Cd${}_{3-x}$Zn${}_x$As${}_2$
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