Chiral anomaly and Weyl orbit in three-dimensional Dirac semimetal Cd 3 As 2 grown on Si.

Preparing Cd ₃ As ₂ , which is a three-dimensional (3D) Dirac semimetal in certain crystal orientation, on Si is highly desirable as such a sample may well be fully compatible with existing Si CMOS technology. However, there is a dearth of such a study regarding Cd ₃ As ₂ films grown on Si showing the chiral anomaly. Here, for the first time , we report the novel preparation and fabrication technique of a Cd ₃ As ₂ (112) film on a Si (111) substrate with a ZnTe (111) buffer layer which explicitly shows the chiral anomaly with a nontrivial Berry's phase of π . Despite the Hall carrier density (n3D≈9.42×1017cm ^-3 ) of our Cd ₃ As ₂ film, which is almost beyond the limit for the portents of a 3D Dirac semimetal to emerge, we observe large linear magnetoresistance in a perpendicular magnetic field and negative magnetoresistance in a parallel magnetic field. These results clearly demonstrate the chiral magnetic effect and 3D Dirac semimetallic behavior in our silicon-based Cd ₃ As ₂ film. Our tailoring growth of Cd ₃ As ₂ on a conventional substrate such as Si keeps the sample quality, while also achieving a low carrier concentration.
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