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Related papers: Valley excitons in two-dimensional semiconductors

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Transition metal dichalcogenide (TMD) monolayers (MLs) exhibit rich photoluminescence spectra associated with interband optical transitions of direct-gap semiconductors. Upon absorption of photons, direct excitons with zero center-of-mass…

The optical properties of atomically thin transition metal dichalcogenide (TMDC) semiconductors are shaped by the emergence of correlated many-body complexes due to strong Coulomb interaction. Exceptional electron-hole exchange predestines…

We study theoretically nonlinear valley polarization dynamics of excitons in atom-thin semiconductors. The presence of significant polarization slows down valley relaxation due to an effective magnetic field resulting from exciton-exciton…

Mesoscale and Nanoscale Physics · Physics 2022-07-20 M. A. Semina , M. M. Glazov , C. Robert , L. Lombez , T. Amand , X. Marie

The optical properties of monolayer transition metal dichalcogenides are dominated by tightly-bound excitons. They form at distinct valleys in reciprocal space, and can interact via the valley-exchange coupling, modifying their dispersion…

The valley degree of freedom of electrons in two-dimensional transition metal dichalcogenides has been extensively studied by theory, optical and optoelectronic experiments. However, generation and detection of pure valley current without…

Mesoscale and Nanoscale Physics · Physics 2019-04-23 Terry Y. T. Hung , Kerem Y. Camsari , Shengjiao Zhang , Pramey Upadhyaya , Zhihong Chen

Monolayer transition metal dichalcogenide (TMDC) crystals, as direct-gap materials with unusually strong light-matter interaction, have attracted much recent attention. In contrast to the initial understanding, the minima of the conduction…

A new frontier in van der Waals twistronics is the development of three-dimensional (3D) supertwisted materials, where each successive atomic layer rotates by the same angle. While two-dimensional (2D) moire systems have been extensively…

We develop an analytically solvable model able to qualitatively explain nonhydrogenic exciton spectra observed recently in two-dimensional (2d) semiconducting transition metal dichalcogenides. Our exciton Hamiltonian explicitly includes…

Mesoscale and Nanoscale Physics · Physics 2016-07-11 Maxim Trushin , Mark Oliver Goerbig , Wolfgang Belzig

Single-layer transition metal dichalcogenides (TMDs) provide a promising material system to explore the electron's valley degree of freedom as a quantum information carrier. The valley degree of freedom in single-layer TMDs can be directly…

Mesoscale and Nanoscale Physics · Physics 2019-10-09 Yanhao Tang , Kin Fai Mak , Jie Shan

The semiconducting single-layer transition metal dichalcogenides have been identified as ideal materials for accessing and manipulating spin- and valley-quantum numbers due to a set of favorable optical selection rules in these materials.…

The polarization analysis of optical transitions in monolayer and bilayer transition-metal dichalcogenides provides invaluable information on the spin and valley (pseudospin) degrees of freedom. To explain optical properties of a given…

Materials Science · Physics 2015-10-06 Hanan Dery , Yang Song

Due to a strong Coulomb interaction, excitons dominate the excitation kinetics in 2D materials. While Coulomb-scattering between electrons has been well studied, the interaction of excitons is more challenging and remains to be explored. As…

Materials Science · Physics 2021-01-27 Daniel Erkensten , Samuel Brem , Ermin Malic

Hybrid exciton in moir\'e superlattices of two-dimensional (2D) semiconductors inherits the electric dipole, strong moir\'e trapping, and stacking optical selection rules from its interlayer part, whereas the intralayer part is intended for…

Mesoscale and Nanoscale Physics · Physics 2025-05-08 Huiyuan Zheng , Ci Li , Hongyi Yu , Wang Yao

Spin-valley coupling in monolayer transition metal dichalcogenides gives rise to valley polarization and coherence effect, limited by intervalley scattering caused by exciton-phonon, exciton-impurity, and electron-hole exchange interaction…

Coulomb bound electron-hole pairs, excitons, govern the optical properties of semi-conducting transition metal dichalcogenides like MoS$_2$ and WSe$_2$. We study optical transitions at the K-point for 2H homobilayer MoS$_2$ in Density…

Light emission from higher-order correlated excitonic states has been recently reported in hBN-encapsulated monolayer WSe2 and WS2 upon optical excitation. These exciton complexes are found to be bound states of excitons residing in…

Mesoscale and Nanoscale Physics · Physics 2019-04-19 Matthias Paur , Aday J. Molina-Mendoza , Rudolf Bratschitsch , Kenji Watanabe , Takashi Taniguchi , Thomas Mueller

Rich valleytronics and diverse defect-induced or interlayer pre-bandgap excitonics have been extensively studied in transition metal dichalcogenides (TMDCs), a system with fascinating optical physics. However, more intense high-energy…

Materials Science · Physics 2021-04-02 Jinhua Hong , Masanori Koshino , Ryosuke Senga , Thomas Pichler , Hua Xu , Kazu Suenaga

We investigate two-photon transitions to the electron-hole scattering continuum in monolayer transition-metal dichalcogenides, and identify two contributions to this nonlinear optical process with opposite circularly polarized valley…

Mesoscale and Nanoscale Physics · Physics 2019-03-14 Pu Gong , Hongyi Yu , Yong Wang , Wang Yao

The growing field of quantum information technology requires propagation of information over long distances with efficient readout mechanisms. Excitonic quantum fluids have emerged as a powerful platform for this task due to their…

Mesoscale and Nanoscale Physics · Physics 2023-07-12 Saroj B. Chand , John M. Woods , Jiamin Quan , Enrique Mejia , Takashi Taniguchi , Kenji Watanabe , Andrea Alù , Gabriele Grosso

Strong spin-orbit coupling and inversion symmetry breaking in transition metal dichalcogenide monolayers yield the intriguing effects of valley-dependent optical selection rules. As such, it is possible to substantially polarize valley…