Enhanced magneto-optical response due to the flat band in nanoribbons made from the alpha - T-3 lattice

Chen, Yan-Ru1,2; Xu, Yong2; Wang, Jun3; Liu, Jun-Feng1,2; Ma, Zhongshui4,5

2019-01-15

10.1103/PhysRevB.99.045420

PHYSICAL REVIEW B   影响因子和分区

2469-9950

2469-9969

We study the optical response of nanoribbons made from the alpha - T-3 lattice under a weak magnetic field in the terahertz to far-infrared regime. It is found that the magnetic field can open a gap in the band structure and induce a new absorption peak with much reduced frequency in metallic armchair ribbons and a class of zigzag ribbons with particular boundaries. This tunable magneto-optical modulation effect is attributed to the interband transitions between the flat band and the propagating bands. By contrast, this magnetic modulation of gap opening and optical conductance is much weaker in metallic armchair graphene ribbons (the case of alpha = 0) in which the flat band is absent. The enhancement in the alpha - T-3 model is analytically investigated and explained within the perturbation theory for metallic armchair ribbons. The magnetic field induced valley degeneracy lifting and valley splitting of the absorption peak are also discussed in the case of zigzag ribbons. These findings pave the way for magneto-optics devices based on the alpha - T-3 model materials.

SCI ; EI

英语

通讯

NBRP of China[2012CB921300]

Materials Science ; Physics

Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000455827100001

AMER PHYSICAL SOC

20191906878693

Magnetic fields ; Modulation ; Nanoribbons ; Optical signal processing ; Perturbation techniques

Magnetism: Basic Concepts and Phenomena:701.2 ; Laser Beam Interactions:744.8 ; Nanotechnology:761 ; Mathematics:921

PHYSICS

Web of Science

1.Guangzhou Univ, Sch Phys & Elect Engn, Dept Phys, Guangzhou 510006, Guangdong, Peoples R China
2.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
3.Southeast Univ, Dept Phys, Nanjing 210096, Jiangsu, Peoples R China
4.Peking Univ, Sch Phys, Beijing 100871, Peoples R China
5.Collaborat Innovat Ctr Quantum Matter, Beijing 100871, Peoples R China

Chen, Yan-Ru,Xu, Yong,Wang, Jun,et al. Enhanced magneto-optical response due to the flat band in nanoribbons made from the alpha - T-3 lattice[J]. PHYSICAL REVIEW B,2019,99(4).

Chen, Yan-Ru,Xu, Yong,Wang, Jun,Liu, Jun-Feng,&Ma, Zhongshui.(2019).Enhanced magneto-optical response due to the flat band in nanoribbons made from the alpha - T-3 lattice.PHYSICAL REVIEW B,99(4).

Chen, Yan-Ru,et al."Enhanced magneto-optical response due to the flat band in nanoribbons made from the alpha - T-3 lattice".PHYSICAL REVIEW B 99.4(2019).