Phase engineering of 1T$'$ and 1T CrS2 and Cr2S3 by MOCVD

Haoyu Bai; Gareth R. M Tainton; Mauro Och; Max Rimmer; Indrajit Maity; Filippo Mione; Khagesh Tanwar; Rongsheng Cai; Joseph Parker; Kho Zhiquan; Ercin C Duran; Evan Tillotson; Sam Sullivan-Allsop; Alexander Eggeman; Siyuan Deng; Dan Bromley; Jack N. Carter-Gartside; Alex Vanstone; Sandrine Heutz; Will R. Branford; Efrén Navarro-Moratalla; Johannes C. Lischner; Sarah Haigh; Cecilia Mattevi

arXiv · 2509.07899

Phase engineering of 1T$'$ and 1T CrS2 and Cr2S3 by MOCVD

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Abstract

Layered Cr-chalcogenides compounds offer a rich range of crystal phases with different magnetic properties some of which have been predicted only but not experimentally verified. Here we demonstrate a previously unreported crystal phase of CrS2, namely the distorted octahedral (1T$'$) structure, synthesized via metal-organic chemical vapour deposition (MOCVD). We achieved the tuneable synthesis of either 1T$'$ or 1T phase CrS2. The structure were identified using polarized Raman spectroscopy, density functional perturbation theory (DFPT), as well as scanning electron diffraction (4D-STEM). 4D-STEM reveals that 1T$'$ crystals grow from an originally nucleated kinetically favoured 1T phase which then transform into the thermodynamically stable 1T$'$ phase. Magneto-optic Kerr imaging reveals that the 1T$'$ CrS2 crystals have soft ferromagnetic nature at low temperature. Our MOCVD growth of complex phases of 2D CrS2 with long-range magnetic order paves the way for the scalable synthesis of 2D magnets for ultrathin magnetic memories for logic-in-memory applications and spintronics.

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Haoyu Bai, Gareth R. M Tainton, Mauro Och, Max Rimmer, Indrajit Maity, Filippo Mione, Khagesh Tanwar, Rongsheng Cai, Joseph Parker, Kho Zhiquan, Ercin C Duran, Evan Tillotson, Sam Sullivan-Allsop, Alexander Eggeman, Siyuan Deng, Dan Bromley, Jack N. Carter-Gartside, Alex Vanstone, Sandrine Heutz, Will R. Branford, Efrén Navarro-Moratalla, Johannes C. Lischner, Sarah Haigh, Cecilia Mattevi. 2025-09-09. Phase engineering of 1T$'$ and 1T CrS2 and Cr2S3 by MOCVD. https://arxiv.org/abs/2509.07899

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