Growth and characterization of CrTe2/PtTe2 bilayers and alloys

Bo-Han Chen^1*, Guan-Yu Chen¹, Han-Yu Hsu¹, Yung-Sung Chen¹, Jhen-Honng Yen¹, Cha-Her Lin¹, Chen-Yu Lien¹, Yu-Chen Chang¹, Li-Wei Tu¹, Paritosh Vilas Wadekar¹

¹Department of Physics and Center of Crystal Research, National Sun Yat-Sen University, Kaohsiung, Taiwan

* Presenter:Bo-Han Chen, email:z73yx7eg5@gmail.com

Transition metal ditellurides (XTe₂) shown novel properties based on the transition metal. For example, if X = Pt, then PtTe₂, is a topological semimetals with an electronic band structure showing massless Dirac fermions and diamagnetic behavior. If X = Cr, then CrTe₂ is an intrinsic ferromagnetic metal, with a colossal anomalous Hall effect, but lacks Dirac fermions. Inducing ferromagnetism in a topological semimetal could be promising for spin based quantum information studies. So, where we study the growth and characterization of CrTe₂, PtTe₂, PtTe₂/CrTe₂, and Pt_1-xCr_xTe₂ alloys. These samples were grown on single crystalline sapphire substrates using atmospheric pressure chemical vapor deposition (APCVD) processes. By tellurization of metallic seed layers of controlled thickness and orientations, we were successful in getting the desired crystalline phases. The samples were characterized using a host of analysis techniques such as X-ray diffraction and reflectivity, Raman spectroscopy, X-ray photoelectron spectroscopy, and magnetometry measurements. The effect of the growth conditions on the crystallinity, morphology, uniformity on the magnetic properties are reported.

Keywords: 2D materials, Dirac semimetal, ferromagnetism, APCVD