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Proposal for valleytronic materials: Ferrovalley metal and valley gapless semiconductor

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Abstract

Valleytronic materials can provide new degrees of freedom to future electronic devices. In this work, the concepts of the ferrovalley metal (FVM) and valley gapless semiconductor (VGS) are proposed, which can be achieved in valleytronic bilayer systems by electric field engineering. In valleytronic bilayer systems, the interaction between out-of-plane ferroelectricity and A-type antiferromagnetism can induce layer-polarized anomalous valley Hall (LP-AVH) effect. The K and −K valleys of FVM are both metallic, and electron and hole carriers simultaneously exist. In the extreme case, the FVM can become VGS by analogizing spin gapless semiconductor (SGS). Moreover, it is proposed that the valley splitting enhancement and valley polarization reversal can be achieved by electric field engineering in valleytronic bilayer systems. Taking the bilayer RuBr2 as an example, our proposal is confirmed by the first-principle calculations. The FVM and VGS can be achieved in bilayer RuBr2 by applying electric field. With appropriate electric field range, increasing electric field can enhance valley splitting, and the valley polarization can be reversed by flipping electric field direction. To effectively tune valley properties by electric field in bilayer systems, the parent monolayer should possess out-of-plane magnetization, and have large valley splitting. Our results shed light on the possible role of electric field in tuning valleytronic bilayer systems, and provide a way to design the ferrovalley-related material by electric field.

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References and notes

  1. X. Xu, W. Yao, D. Xiao, and T. F. Heinz, Spin and pseudospins in layered transition metal dichalcogenides, Nat. Phys. 10(5), 343 (2014)

    Article  Google Scholar 

  2. Y. Liu, C. S. Lian, Y. Li, Y. Xu, and W. Duan, Pseudospins and topological effects of phonons in a Kekulé lattice, Phys. Rev. Lett. 119(25), 255901 (2017)

    Article  ADS  Google Scholar 

  3. M. Zeng, Y. Xiao, J. Liu, K. Yang, and L. Fu, Exploring two-dimensional materials toward the next-generation circuits: from monomer design to assembly control, Chem. Rev. 118(13), 6236 (2018)

    Article  Google Scholar 

  4. K. F. Mak, K. He, J. Shan, and T. F. Heinz, Control of valley polarization in monolayer MoS2 by optical helicity, Nat. Nanotechnol. 7(8), 494 (2012)

    Article  ADS  Google Scholar 

  5. D. MacNeill, C. Heikes, K. F. Mak, Z. Anderson, A. Kormányos, V. Zólyomi, J. Park, and D. C. Ralph, Breaking of valley degeneracy by magnetic field in monolayer MoSe2, Phys. Rev. Lett. 114(3), 037401 (2015)

    Article  ADS  Google Scholar 

  6. H. Zeng, J. Dai, W. Yao, D. Xiao, and X. Cui, Valley polarization in MoS2 monolayers by optical pumping, Nat. Nanotechnol. 7, 490 (2012)

    Article  ADS  Google Scholar 

  7. A. Srivastava, M. Sidler, A. V. Allain, D. S. Lembke, A. Kis, and A. Imamoglu, Valley Zeeman effect in elementary optical excitations of monolayer WSe2, Nat. Phys. 11(2), 141 (2015)

    Article  Google Scholar 

  8. C. Zhao, T. Norden, P. Zhang, P. Zhao, Y. Cheng, F. Sun, J. P. Parry, P. Taheri, J. Wang, Y. Yang, T. Scrace, K. Kang, S. Yang, G. Miao, R. Sabirianov, G. Kioseoglou, W. Huang, A. Petrou, and H. Zeng, Enhanced valley splitting in monolayer WSe2 due to magnetic exchange field, Nat. Nanotechnol. 12(8), 757 (2017)

    Article  Google Scholar 

  9. H. Zeng, J. Dai, W. Yao, D. Xiao, and X. Cui, Valley polarization in MoS2 monolayers by optical pumping, Nat. Nanotechnol. 7(8), 490 (2012)

    Article  ADS  Google Scholar 

  10. J. R. Schaibley, H. Yu, G. Clark, P. Rivera, J. S. Ross, K. L. Seyler, W. Yao, and X. Xu, Valleytronics in 2D materials, Nat. Rev. Mater. 1(11), 16055 (2016)

    Article  ADS  Google Scholar 

  11. M. S. Mrudul, Á. Jiménez-Galán, M. Ivanov, and G. Dixit, Light-induced valleytronics in pristine graphene, Optica 8(3), 422 (2021)

    Article  ADS  Google Scholar 

  12. M. S. Mrudul and G. Dixit, Controlling valley-polarisation in graphene via tailored light pulses, J. Phys. At. Mol. Opt. Phys. 54(22), 224001 (2021)

    Article  ADS  Google Scholar 

  13. W. Y. Tong, S. J. Gong, X. Wan, and C. G. Duan, Concepts of ferrovalley material and anomalous valley Hall effect, Nat. Commun. 7(1), 13612 (2016)

    Article  ADS  Google Scholar 

  14. H. Hu, W. Y. Tong, Y. H. Shen, X. Wan, and C. G. Duan, Concepts of the half-valley-metal and quantum anomalous valley Hall effect, npj Comput. Mater. 6, 129 (2020)

    Article  ADS  Google Scholar 

  15. S. D. Guo, J. X. Zhu, W. Q. Mu, and B. G. Liu, Possible way to achieve anomalous valley Hall effect by piezoelectric effect in a GdCl2 monolayer, Phys. Rev. B 104(22), 224428 (2021)

    Article  ADS  Google Scholar 

  16. X. Y. Feng, X. L. Xu, Z. L. He, R. Peng, Y. Dai, B. B. Huang, and Y. D. Ma, Valley-related multiple Hall effect in monolayer VSi2P4, Phys. Rev. B 104(7), 075421 (2021)

    Article  ADS  Google Scholar 

  17. Q. R. Cui, Y. M. Zhu, J. H. Liang, P. Cui, and H. X. Yang, Spin-valley coupling in a two-dimensional VSi2N4 monolayer, Phys. Rev. B 103(8), 085421 (2021)

    Article  ADS  Google Scholar 

  18. X. Zhou, R. Zhang, Z. Zhang, W. Feng, Y. Mokrousov, and Y. Yao, Sign-reversible valley-dependent Berry phase effects in 2D valley-half-semiconductors, npj Comput. Mater. 7, 160 (2021)

    Article  ADS  Google Scholar 

  19. I. Khan, B. Marfoua, and J. Hong, Electric field induced giant valley polarization in two dimensional ferromagnetic WSe2/CrSnSe3 heterostructure, npj 2D Mater. Appl. 5, 10 (2021)

    Article  Google Scholar 

  20. H. X. Cheng, J. Zhou, W. Ji, Y. N. Zhang, and Y. P. Feng, Two-dimensional intrinsic ferrovalley GdI2 with large valley polarization, Phys. Rev. B 103(12), 125121 (2021)

    Article  ADS  Google Scholar 

  21. R. Li, J. W. Jiang, W. B. Mi, and H. L. Bai, Room temperature spontaneous valley polarization in two-dimensional FeClBr monolayer, Nanoscale 13(35), 14807 (2021)

    Article  Google Scholar 

  22. K. Sheng, Q. Chen, H. K. Yuan, and Z. Y. Wang, Monolayer CeI2: An intrinsic room-temperature ferrovalley semiconductor, Phys. Rev. B 105(7), 075304 (2022)

    Article  ADS  Google Scholar 

  23. P. Jiang, L. L. Kang, Y. L. Li, X. H. Zheng, Z. Zeng, and S. Sanvito, Prediction of the two-dimensional Janus ferrovalley material LaBrI, Phys. Rev. B 104(3), 035430 (2021)

    Article  ADS  Google Scholar 

  24. R. Peng, Y. Ma, X. Xu, Z. He, B. Huang, and Y. Dai, Intrinsic anomalous valley Hall effect in single-layer Nb3I8, Phys. Rev. B 102(3), 035412 (2020)

    Article  ADS  Google Scholar 

  25. K. Sheng, B. K. Zhang, H. K. Yuan, and Z. Y. Wang, Strain-engineered topological phase transitions in ferrovalley 2H−RuCl2 monolayer, Phys. Rev. B 105(19), 195312 (2022)

    Article  ADS  Google Scholar 

  26. S. D. Guo, J. X. Zhu, M. Y. Yin, and B. G. Liu, Substantial electronic correlation effects on the electronic properties in a Janus FeClF monolayer, Phys. Rev. B 105(10), 104416 (2022)

    Article  ADS  Google Scholar 

  27. S. D. Guo, W. Q. Mu, and B. G. Liu, Valley-polarized quantum anomalous Hall insulator in monolayer RuBr2, 2D Mater. 9, 035011 (2022)

    Article  Google Scholar 

  28. H. Huan, Y. Xue, B. Zhao, G. Y. Gao, H. R. Bao, and Z. Q. Yang, Strain-induced half-valley metals and topological phase transitions in MBr2 monolayers (M = Ru, Os), Phys. Rev. B 104(16), 165427 (2021)

    Article  ADS  Google Scholar 

  29. S. D. Guo, Y. L. Tao, W. Q. Mu, and B. G. Liu, Correlation-driven threefold topological phase transition in monolayer OsBr2, Front. Phys. 18(3), 33304 (2023)

    Article  ADS  Google Scholar 

  30. S. D. Guo, Y. L. Tao, H. T. Guo, Z. Y. Zhao, B. Wang, G. Z. Wang, and X. T. Wang, Possible electronic state quasi-half-valley metal in a VGe2P4 monolayer, Phys. Rev. B 107(5), 054414 (2023)

    Article  ADS  Google Scholar 

  31. X. L. Wang, Proposal for a new class of materials: Spin gapless semiconductors, Phys. Rev. Lett. 100(15), 156404 (2008)

    Article  ADS  Google Scholar 

  32. T. Zhang, X. L. Xu, B. B. Huang, Y. Dai, L. Z. Kou, and Y. D. Ma, Layer-polarized anomalous Hall effects in valleytronic van der Waals bilayers, Mater. Horiz. 10(2), 483 (2023)

    Article  Google Scholar 

  33. X. Liu, A. P. Pyatakov, and W. Ren, Magnetoelectric coupling in multiferroic bilayer VS2, Phys. Rev. Lett. 125(24), 247601 (2020)

    Article  ADS  Google Scholar 

  34. A. O. Fumega and J. L. Lado, Ferroelectric valley valves with graphene/MoTe2 van der Waals heterostructures, Nanoscale 15(5), 2181 (2023)

    Article  Google Scholar 

  35. W. Y. Tong and C. G. Duan, Electrical control of the anomalous valley Hall effect in antiferrovalley bilayers, npj Quantum Mater. 2, 47 (2017)

    Article  ADS  Google Scholar 

  36. P. Hohenberg and W. Kohn, Inhomogeneous electron gas, Phys. Rev. 136(3B), B864 (1964)

    Article  ADS  MathSciNet  Google Scholar 

  37. W. Kohn and L. J. Sham, Self-consistent equations including exchange and correlation effects, Phys. Rev. 140(4A), A1133 (1965)

    Article  ADS  MathSciNet  Google Scholar 

  38. G. Kresse, Ab initio molecular dynamics for liquid metals, J. Non-Cryst. Solids 193, 222 (1995)

    Article  ADS  Google Scholar 

  39. G. Kresse and J. Furthmüller, Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set, Comput. Mater. Sci. 6(1), 15 (1996)

    Article  Google Scholar 

  40. G. Kresse and D. Joubert, From ultrasoft pseudopotentials to the projector augmented-wave method, Phys. Rev. B 59(3), 1758 (1999)

    Article  ADS  Google Scholar 

  41. J. P. Perdew, K. Burke, and M. Ernzerhof, Generalized gradient approximation made simple, Phys. Rev. Lett. 77(18), 3865 (1996)

    Article  ADS  Google Scholar 

  42. M. Cococcioni and S. de Gironcoli, Linear response approach to the calculation of the effective interaction parameters in the LDA + U method, Phys. Rev. B 71(3), 035105 (2005)

    Article  ADS  Google Scholar 

  43. See Supplemental Material for calculating U; crystal structures; energy difference between FM and AFM and MAE as a function of E; the related energy band structures.

  44. S. L. Dudarev, G. A. Botton, S. Y. Savrasov, C. J. Humphreys, and A. P. Sutton, Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+ U study, Phys. Rev. B 57(3), 1505 (1998)

    Article  ADS  Google Scholar 

  45. S. Grimme, S. Ehrlich, and L. Goerigk, Effect of the damping function in dispersion corrected density functional theory, J. Comput. Chem. 32(7), 1456 (2011)

    Article  Google Scholar 

  46. T. Fukui, Y. Hatsugai, and H. Suzuki, Chern numbers in discretized Brillouin zone: Efficient method of computing (spin) Hall conductances, J. Phys. Soc. Jpn. 74(6), 1674 (2005)

    Article  ADS  Google Scholar 

  47. H. J. Kim, URL: github.com/Infant83/VASPBERRY (2018)

  48. H. J. Kim, C. Li, J. Feng, J. H. Cho, and Z. Zhang, Competing magnetic orderings and tunable topological states in two-dimensional hexagonal organometallic lattices, Phys. Rev. B 93, 041404(R) (2016)

    Article  ADS  Google Scholar 

  49. To easily meet energy convergence criterion, the parameter DIPOL=0.5 0.5 0.5 is set, and the convergent charge density under small electric field gradually feeds to the calculations with large electric field.

  50. P. Zhao, Y. Dai, H. Wang, B. B. Huang, and Y. D. Ma, Intrinsic valley polarization and anomalous valley hall effect in single-layer 2H−FeCl2, Chem. Phys. Mater. 1(1), 56 (2022)

    Google Scholar 

  51. R. Li, J. W. Jiang, W. B. Mi, and H. L. Bai, Room temperature spontaneous valley polarization in two-dimensional FeClBr monolayer, Nanoscale 13(35), 14807 (2021)

    Article  Google Scholar 

  52. D. Xiao, M. C. Chang, and Q. Niu, Berry phase effects on electronic properties, Rev. Mod. Phys. 82(3), 1959 (2010)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  53. B. I. Weintrub, Y. L. Hsieh, S. Kovalchuk, J. N. Kirchhof, K. Greben, and K. I. Bolotin, Generating intense electric fields in 2D materials by dual ionic gating, Nat. Commun. 13(1), 6601 (2022)

    Article  ADS  Google Scholar 

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Acknowledgements

This work was supported by Natural Science Basis Research Plan in Shaanxi Province of China (No. 2020JQ-845). Y.S.A. is supported by the Singapore Ministry of Education Academic Research Fund Tier 2 (Award No. MOE-T2EP50221-0019). We are grateful to Shanxi Supercomputing Center of China, and the calculations were performed on TianHe-2.

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Correspondence to San-Dong Guo.

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Guo, SD., Tao, YL., Wang, G. et al. Proposal for valleytronic materials: Ferrovalley metal and valley gapless semiconductor. Front. Phys. 19, 23302 (2024). https://doi.org/10.1007/s11467-023-1334-y

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