Charge-tuneable biexciton complexes in monolayer WSe2

被引：202

作者：

Barbone, Matteo ^{[1
,2
]}

Montblanch, Alejandro R. -P. ^{[1
]}

Kara, Dhiren M. ^{[1
]}

Palacios-Berraquero, Carmen ^{[1
]}

Cadore, Alisson R. ^{[2
]}

De Fazio, Domenico ^{[2
]}

Pingault, Benjamin ^{[1
]}

Mostaani, Elaheh ^{[2
]}

Li, Han ^{[3
]}

Chen, Bin ^{[3
]}

Watanabe, Kenji ^{[4
]}

Taniguchi, Takashi ^{[4
]}

Tongay, Sefaattin ^{[3
]}

Wang, Gang ^{[2
]}

Ferrari, Andrea C. ^{[2
]}

Atature, Mete ^{[1
]}

机构：

[1] Univ Cambridge, Cavendish Lab, JJ Thomson Ave, Cambridge CB3 0HE, England

[2] Univ Cambridge, Cambridge Graphene Ctr, Cambridge CB3 0FA, England

[3] Arizona State Univ, Sch Engn Matter Transport & Energy, Tempe, AZ 85287 USA

[4] Natl Inst Mat Sci, Tsukuba, Ibaraki 3050034, Japan

来源：

NATURE COMMUNICATIONS | 2018年 / 9卷

基金：

英国工程与自然科学研究理事会;

关键词：

VALLEY POLARIZATION; EXCITONS; TRIONS; MOS2;

D O I：

10.1038/s41467-018-05632-4

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Monolayer transition metal dichalcogenides have strong Coulomb-mediated many-body interactions. Theoretical studies have predicted the existence of numerous multi-particle excitonic states. Two-particle excitons and three-particle trions have been identified by their optical signatures. However, more complex states such as biexcitons have been elusive due to limited spectral quality of the optical emission. Here, we report direct evidence of two biexciton complexes in monolayer tungsten diselenide: the four-particle neutral biexciton and the five-particle negatively charged biexciton. We distinguish these states by power-dependent photoluminescence and demonstrate full electrical switching between them. We determine the band states of the elementary particles comprising the biexcitons through magneto-optical spectroscopy. We also resolve a splitting of 2.5 meV for the neutral biexciton, which we attribute to the fine structure, providing reference for subsequent studies. Our results unveil the nature of multi-exciton complexes in transitionmetal dichalcogenides and offer direct routes towards deterministic control in many-body quantum phenomena.

引用

页数：6

共 49 条

[1] Magnetic control of valley pseudospin in monolayer WSe2 [J].