Pan Xiaoguang, Yang Tianwen, Bai Hangxin, Peng Jiangbo, Li Lujie, Jing Fangli, Qiu Hailong, Liu Hongjun, Hu Zhanggui
Tianjin Key Laboratory of Functional Crystal Materials, Institute of Functional Crystals, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
Nanomaterials (Basel). 2023 Jun 5;13(11):1806. doi: 10.3390/nano13111806.
1T-TaS has attracted much attention recently due to its abundant charge density wave phases. In this work, high-quality two-dimensional 1T-TaS crystals were successfully synthesized by a chemical vapor deposition method with controllable layer numbers, confirmed by the structural characterization. Based on the as-grown samples, their thickness-dependency nearly commensurate charge density wave/commensurate charge density wave phase transitions was revealed by the combination of the temperature-dependent resistance measurements and Raman spectra. The phase transition temperature increased with increasing thickness, but no apparent phase transition was found on the 2~3 nm thick crystals from temperature-dependent Raman spectra. The transition hysteresis loops due to temperature-dependent resistance changes of 1T-TaS can be used for memory devices and oscillators, making 1T-TaS a promising material for various electronic applications.
由于其丰富的电荷密度波相，1T-TaS最近备受关注。在这项工作中，通过化学气相沉积法成功合成了具有可控层数的高质量二维1T-TaS晶体，并通过结构表征得到证实。基于生长的样品，通过结合温度依赖电阻测量和拉曼光谱，揭示了它们厚度依赖性的近 commensurate电荷密度波/commensurate电荷密度波相变。相变温度随厚度增加而升高，但从温度依赖拉曼光谱来看，在2至3纳米厚的晶体上未发现明显的相变。1T-TaS因温度依赖电阻变化而产生的转变滞后回线可用于存储器件和振荡器，使1T-TaS成为各种电子应用的有前途的材料。
