中国物理B ›› 2019, Vol. 28 ›› Issue (10): 107502-107502.doi: 10.1088/1674-1056/ab3a91

所属专题: TOPICAL REVIEW — A celebration of the 100th birthday of Kun Huang

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Electrical transport and optical properties of Cd3As2 thin films

Yun-Kun Yang(杨运坤), Fa-Xian Xiu(修发贤), Feng-Qiu Wang(王枫秋), Jun Wang(王军), Yi Shi(施毅)   

  1. 1 Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China;
    2 State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China;
    3 School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China;
    4 School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China;
    5 State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China;
    6 National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China
  • 收稿日期:2019-07-17 修回日期:2019-08-08 出版日期:2019-10-05 发布日期:2019-10-05
  • 通讯作者: Yi Shi E-mail:yshi@nju.edu.cn
  • 基金资助:
    Project supported by the National Key Research and Development Program of China (Grant Nos. 2017YFA0303302 and 2018YFA0305601) and the National Natural Science Foundation of China (Grant Nos. 61322407, 11474058, 61674040, and 11874116).

Electrical transport and optical properties of Cd3As2 thin films

Yun-Kun Yang(杨运坤)1,2, Fa-Xian Xiu(修发贤)1,2, Feng-Qiu Wang(王枫秋)1,3, Jun Wang(王军)4,5, Yi Shi(施毅)1,3,6   

  1. 1 Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China;
    2 State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China;
    3 School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China;
    4 School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China;
    5 State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China;
    6 National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China
  • Received:2019-07-17 Revised:2019-08-08 Online:2019-10-05 Published:2019-10-05
  • Contact: Yi Shi E-mail:yshi@nju.edu.cn
  • Supported by:
    Project supported by the National Key Research and Development Program of China (Grant Nos. 2017YFA0303302 and 2018YFA0305601) and the National Natural Science Foundation of China (Grant Nos. 61322407, 11474058, 61674040, and 11874116).

摘要: Cd3As2, as a three-dimensional (3D) topological Dirac semimetal, has attracted wide attention due to its unique physical properties originating from the 3D massless Dirac fermions. While many efforts have been devoted to the exploration of novel physical phenomena such as chiral anomaly and phase transitions by using bulk crystals, the development of high-quality and large-scale thin films becomes necessary for practical electronic and optical applications. Here, we report our recent progress in developing single-crystalline thin films with improved quality and their optical devices including Cd3As2-based heterojunctions and ultrafast optical switches. We find that a post-annealing process can significantly enhance the crystallinity of Cd3As2 in both intrinsic and Zn-doped thin films. With excellent characteristics of high mobility and linear band dispersion, Cd3As2 exhibits a good optical response in the visible-to-mid-infrared range due to an advantageous optical absorption, which is reminiscent of 3D graphene. It also behaves as an excellent saturable absorber in the mid-infrared regime. Through the delicate doping process in this material system, it may further open up the long-sought parameter space crucial for the development of compact and high-performance mid-infrared ultrafast sources.

关键词: topological Dirac semimetals, thin films, photodetectors, ultra-fast optical switches

Abstract: Cd3As2, as a three-dimensional (3D) topological Dirac semimetal, has attracted wide attention due to its unique physical properties originating from the 3D massless Dirac fermions. While many efforts have been devoted to the exploration of novel physical phenomena such as chiral anomaly and phase transitions by using bulk crystals, the development of high-quality and large-scale thin films becomes necessary for practical electronic and optical applications. Here, we report our recent progress in developing single-crystalline thin films with improved quality and their optical devices including Cd3As2-based heterojunctions and ultrafast optical switches. We find that a post-annealing process can significantly enhance the crystallinity of Cd3As2 in both intrinsic and Zn-doped thin films. With excellent characteristics of high mobility and linear band dispersion, Cd3As2 exhibits a good optical response in the visible-to-mid-infrared range due to an advantageous optical absorption, which is reminiscent of 3D graphene. It also behaves as an excellent saturable absorber in the mid-infrared regime. Through the delicate doping process in this material system, it may further open up the long-sought parameter space crucial for the development of compact and high-performance mid-infrared ultrafast sources.

Key words: topological Dirac semimetals, thin films, photodetectors, ultra-fast optical switches

中图分类号:  (Magnetotransport phenomena; materials for magnetotransport)

  • 75.47.-m
75.70.Tj (Spin-orbit effects) 73.43.-f (Quantum Hall effects)