中国物理B ›› 2018, Vol. 27 ›› Issue (2): 27101-027101.doi: 10.1088/1674-1056/27/2/027101

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Electronic structures and optical properties of HfO2-TiO2 alloys studied by first-principles GGA+ U approach

Jin-Ping Li(李金平), Song-He Meng(孟松鹤), Cheng Yang(杨程), Han-Tao Lu(陆汉涛), Takami Tohyama(遠山貴巳)   

  1. 1. Center for Composite Materials and Structure, Harbin Institute of Technology, Harbin 150080, China;
    2. Center for Interdisciplinary Studies & Key Laboratory for Magnetism and Magnetic Materials of the MoE, Lanzhou University, Lanzhou 730000, China;
    3. Department of Applied Physics, Tokyo University of Science, Tokyo 125-8585, Japan
  • 收稿日期:2017-08-29 修回日期:2017-11-05 出版日期:2018-02-05 发布日期:2018-02-05
  • 通讯作者: Jin-Ping Li E-mail:lijinping@hit.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11672087, 11502058, and 11402252).

Electronic structures and optical properties of HfO2-TiO2 alloys studied by first-principles GGA+ U approach

Jin-Ping Li(李金平)1, Song-He Meng(孟松鹤)1, Cheng Yang(杨程)1, Han-Tao Lu(陆汉涛)2, Takami Tohyama(遠山貴巳)3   

  1. 1. Center for Composite Materials and Structure, Harbin Institute of Technology, Harbin 150080, China;
    2. Center for Interdisciplinary Studies & Key Laboratory for Magnetism and Magnetic Materials of the MoE, Lanzhou University, Lanzhou 730000, China;
    3. Department of Applied Physics, Tokyo University of Science, Tokyo 125-8585, Japan
  • Received:2017-08-29 Revised:2017-11-05 Online:2018-02-05 Published:2018-02-05
  • Contact: Jin-Ping Li E-mail:lijinping@hit.edu.cn
  • About author:71.15.-m; 71.15.Mb; 78.20.Ci; 78.20.Fm
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11672087, 11502058, and 11402252).

摘要: The phase diagram of HfO2-TiO2 system shows that when Ti content is less than 33.0 mol%, HfO2-TiO2 system is monoclinic; when Ti content increases from 33.0 mol% to 52.0 mol%, it is orthorhombic; when Ti content reaches more than 52.0 mol%, it presents rutile phase. So, we choose the three phases of HfO2-TiO2 alloys with different Ti content values. The electronic structures and optical properties of monoclinic, orthorhombic and rutile phases of HfO2-TiO2 alloys are obtained by the first-principles generalized gradient approximation (GGA)+U approach, and the effects of Ti content and crystal structure on the electronic structures and optical properties of HfO2-TiO2 alloys are investigated. By introducing the Coulomb interactions of 5d orbitals on Hf atom (U1d), those of 3d orbitals on Ti atom (U2d), and those of 2p orbitals on O atom (Up) simultaneously, we can improve the calculation values of the band gaps, where U1d, U2d, and Up values are 8.0 eV, 7.0 eV, and 6.0 eV for both the monoclinic phase and orthorhombic phase, and 8.0 eV, 7.0 eV, and 3.5 eV for the rutile phase. The electronic structures and optical properties of the HfO2-TiO2 alloys calculated by GGA+U1d (U1d=8.0 eV)+U2d (U2d=7.0 eV)+Up (Up=6.0 eV or 3.5 eV) are compared with available experimental results.

关键词: HfO2-TiO2 alloys, GGA+U, electronic structure, optical properties

Abstract: The phase diagram of HfO2-TiO2 system shows that when Ti content is less than 33.0 mol%, HfO2-TiO2 system is monoclinic; when Ti content increases from 33.0 mol% to 52.0 mol%, it is orthorhombic; when Ti content reaches more than 52.0 mol%, it presents rutile phase. So, we choose the three phases of HfO2-TiO2 alloys with different Ti content values. The electronic structures and optical properties of monoclinic, orthorhombic and rutile phases of HfO2-TiO2 alloys are obtained by the first-principles generalized gradient approximation (GGA)+U approach, and the effects of Ti content and crystal structure on the electronic structures and optical properties of HfO2-TiO2 alloys are investigated. By introducing the Coulomb interactions of 5d orbitals on Hf atom (U1d), those of 3d orbitals on Ti atom (U2d), and those of 2p orbitals on O atom (Up) simultaneously, we can improve the calculation values of the band gaps, where U1d, U2d, and Up values are 8.0 eV, 7.0 eV, and 6.0 eV for both the monoclinic phase and orthorhombic phase, and 8.0 eV, 7.0 eV, and 3.5 eV for the rutile phase. The electronic structures and optical properties of the HfO2-TiO2 alloys calculated by GGA+U1d (U1d=8.0 eV)+U2d (U2d=7.0 eV)+Up (Up=6.0 eV or 3.5 eV) are compared with available experimental results.

Key words: HfO2-TiO2 alloys, GGA+U, electronic structure, optical properties

中图分类号:  (Methods of electronic structure calculations)

  • 71.15.-m
71.15.Mb (Density functional theory, local density approximation, gradient and other corrections) 78.20.Ci (Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)) 78.20.Fm (Birefringence)