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Related papers: Valley excitons in two-dimensional semiconductors

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In atomically thin transition metal dichalcogenides (TMDs), reduced dielectric screening of the Coulomb interaction leads to strongly correlated many-body states, including excitons and trions, that dominate the optical properties.…

In crystals, energy band extrema in momentum space can be identified by their valley index. The internal quantum degree of freedom associated with valley pseudospin indices can act as a useful information carrier analogous to electronic…

Magnetized ferromagnetic disks or wires support strong inhomogeneous fields in their borders. Such magnetic fields create an effective potential, due to Zeeman and diamagnetic contributions, that can localize charge carriers. For the case…

Mesoscale and Nanoscale Physics · Physics 2024-03-08 A. J. Chaves , D. R. da Costa , F. M. Peeters , Nuno M. R. Peres

Excitons, composite electron-hole quasiparticles, are known to play an important role in optoelectronic phenomena in many semiconducting materials. Recent experiments and theory indicate that the band-gap optics of the newly discovered…

Mesoscale and Nanoscale Physics · Physics 2015-09-02 Yuri N. Gartstein , Xiao Li , Chuanwei Zhang

In monolayers of transition metal dichalcogenides the nonlocal nature of the effective dielectric screening leads to large binding energies of excitons. Additional lateral confinement gives rise to exciton localization in quantum dots. By…

Mesoscale and Nanoscale Physics · Physics 2021-03-16 Anvar S. Baimuratov , Alexander Högele

Two-dimensional group-VI transition metal dichalcogenide semiconductors, such as MoS2, WSe2 and others, exhibit strong light-matter coupling and possess direct band gaps in the infrared and visible spectral regimes, making them potentially…

Mesoscale and Nanoscale Physics · Physics 2020-03-03 Thomas Mueller , Ermin Malic

We show theoretically that two-dimensional direct-gap semiconductors with a valley degree of freedom, including monolayer transition-metal dichalcogenides and gapped bilayer graphene, have a longitudinal magnetoconductivity contribution…

Mesoscale and Nanoscale Physics · Physics 2020-02-07 Akihiko Sekine , Allan H. MacDonald

In monolayers of the semiconducting transition metal dichalcogenides, the electron-hole exchange interaction splits the exciton dispersion into a massive transverse branch, and a longitudinal branch that has very light or even zero mass…

Mesoscale and Nanoscale Physics · Physics 2021-12-22 Xu-Chen Yang , Hongyi Yu , Wang Yao

Excitons in monolayer semiconductors have large optical transition dipole for strong coupling with light field. Interlayer excitons in heterobilayers, with layer separation of electron and hole components, feature large electric dipole that…

Mesoscale and Nanoscale Physics · Physics 2019-03-07 Wei-Ting Hsu , Bo-Han Lin , Li-Syuan Lu , Ming-Hao Lee , Ming-Wen Chu , Lain-Jong Li , Wang Yao , Wen-Hao Chang , Chih-Kang Shih

One of the most striking features of novel 2D semiconductors (e.g., transition metal dichalcogenide monolayers or phosphorene) is a strong Coulomb interaction between charge carriers resulting in large excitonic effects. In particular, this…

Mesoscale and Nanoscale Physics · Physics 2015-11-18 Kirill A. Velizhanin , Avadh Saxena

Monolayer transition metal dichalcogenides (TMDs) exhibit a remarkably strong Coulomb interaction that manifests in tightly bound excitons. Due to the complex electronic band structure exhibiting several spin-split valleys in the conduction…

Controlling excitons at the nanoscale in semiconductor materials represents a formidable challenge in the fields of quantum photonics and optoelectronics. Achieving this control holds great potential for unlocking strong exciton-exciton…

The optical properties of transition metal dichalcogenide monolayers are widely dominated by excitons, Coulomb-bound electron-hole pairs. These quasi-particles exhibit giant oscillator strength and give rise to narrow-band, well-pronounced…

Mesoscale and Nanoscale Physics · Physics 2018-07-13 Christian Schneider , Mikhail M. Glazov , Tobias Korn , Sven Höfling , Bernhard Urbaszek

Momentum-indirect excitons composed of electrons and holes in different valleys define optoelectronic properties of many semiconductors, but are challenging to detect due to their weak coupling to light. The identification of an excitons'…

Transition-metal dichalcogenides can be easily produced as atomically thin sheets, exhibiting the possibility to optically polarize and read out the valley pseudospin of extremely stable excitonic quasiparticles present in these 2D…

Valley pseudospin in two-dimensional (2D) transition-metal dichalcogenides (TMDs) allows optical control of spin-valley polarization and intervalley quantum coherence. Defect states in TMDs give rise to new exciton features and…

Two-dimensional excitons formed in quantum materials such as monolayer transition-metal dichalcogenides and their strong light-matter interaction have attracted unrivalled attention by the research community due to their extraordinarily…

Mesoscale and Nanoscale Physics · Physics 2018-12-31 Lorenz Maximilian Schneider , Shanece Esdaille , Daniel Rhodes , Katayun Barmak , James Hone , Arash Rahimi-Iman

Excitons dominate the optical response of two-dimensional (2D) semiconductors. Strong interactions produce peculiar excitonic complexes, which provide a testing ground for exciton and quantum many-body theories. Here, we report a hitherto…

In monolayers of semiconducting transition metal dichalcogenides, the light helicity ($\sigma^+$ or $\sigma^-$) is locked to the valley degree of freedom, leading to the possibility of optical initialization of distinct valley populations.…

Mesoscale and Nanoscale Physics · Physics 2016-05-25 T. Smoleński , M. Goryca , M. Koperski , C. Faugeras , T. Kazimierczuk , K. Nogajewski , P. Kossacki , M. Potemski

Excitons in bilayer transition metal dichalcogenides (2L-TMDs) are Coulomb-bound electron/hole pairs that can be viewed as broadly tunable analogs of atomic or molecular systems. Here, we study the properties of 2L-TMD excitons under strong…

Mesoscale and Nanoscale Physics · Physics 2023-03-20 S. Kovalchuk , K. Greben , A. Kumar , S. Pessel , K. Watanabe , T. Taniguchi , D. Christiansen , M. Selig , A. Knorr , K. I. Bolotin