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Related papers: Valley excitons in two-dimensional semiconductors

200 papers

Transition metal dichalcogenides represent an ideal testbed to study excitonic effects, spin-related phenomena and fundamental light-matter coupling in nanoscopic condensed matter systems. In particular, the valley degree of freedom, which…

Mesoscale and Nanoscale Physics · Physics 2017-05-16 N. Lundt , P. Nagler , A. Nalitov , S. Klembt , M. Wurdack , S. Stoll , T. H. Harder , S. Betzold , V. Baumann , A. V. Kavokin , C. Schüller , T. Korn , S. Höfling , C. Schneider

Monolayer transition metal dichalcogenids (TMDs) feature valley degree of freedom, giant spin-orbit coupling and spin-valley locking. These exotic natures stimulate efforts of exploring the potential applications in conceptual spintronics,…

Mesoscale and Nanoscale Physics · Physics 2017-06-28 Tengfei Yan , Siyuan Yang , Dian Li , Xiaodong Cui

Interactions between two excitons can result in the formation of bound quasiparticles, known as biexcitons. Their properties are determined by the constituent excitons, with orbital and spin states resembling those of atoms. Monolayer…

Mesoscale and Nanoscale Physics · Physics 2015-09-23 Edbert J. Sie , Alex J. Frenzel , Yi-Hsien Lee , Jing Kong , Nuh Gedik

Monolayer (1L) transition metal dichalcogenides (TMDCs) are attractive materials for several optoelectronic applications because of their strong excitonic resonances and valley-selective response. Valley excitons in 1L-TMDCs are formed at…

Optics · Physics 2018-05-30 Alex Krasnok , Andrea Alu

We study the interface exciton at lateral type II heterojunctions of monolayer transition metal dichalcogenides (TMDs), where the electron and hole prefer to stay at complementary sides of the junction. We find that the 1D interface exciton…

Mesoscale and Nanoscale Physics · Physics 2018-09-26 Ka Wai Lau , Calvin , Zhirui Gong , Hongyi Yu , Wang Yao

The newly discovered valley degree of freedom in atomically thin two-dimensional transition metal dichalcogenides (TMD) offers a promising platform to explore rich nonlinear physics, such as spinor Bose-Einstein condensate (BEC) and novel…

Mesoscale and Nanoscale Physics · Physics 2023-01-24 Pasquale Cilibrizzi , Xiaoze Liu , Peiyao Zhang , Chenzhe Wang , Quanwei Li , Sui Yang , Xiang Zhang

Because of the reduced dielectric screening and enhanced Coulomb interactions, two-dimensional (2D) materials like phosphorene and transition metal dichalcogenides (TMDs) exhibit strong excitonic effects, resulting in fascinating…

Materials Science · Physics 2019-11-04 Xiaoyang Zheng , Xian Zhang

Electron-hole exchange interaction in two-dimensional transition metal dichalcogenides is extremely strong due to the dimension reduction, which promises valley-superposed excitonic states with linearly polarized optical emissions. However,…

Mesoscale and Nanoscale Physics · Physics 2024-12-11 Qiutong Wang , Ci Li , Qingjun Tong

We show that, because of the inevitable twist and lattice mismatch in heterobilayers of transition metal dichalcogenides, interlayer excitons have six-fold degenerate light cones anomalously located at finite velocities on the parabolic…

Mesoscale and Nanoscale Physics · Physics 2015-11-05 Hongyi Yu , Yong Wang , Qingjun Tong , Xiaodong Xu , Wang Yao

Monolayer group VI transition metal dichalcogenides have recently emerged as semiconducting alternatives to graphene in which the true two-dimensionality (2D) is expected to illuminate new semiconducting physics. Here we investigate…

Mesoscale and Nanoscale Physics · Physics 2014-03-05 Jason S Ross , Sanfeng Wu , Hongyi Yu , Nirmal J Ghimire , Aaron M Jones , Grant Aivazian , Jiaqiang Yan , David G. Mandrus , Di Xiao , Wang Yao , Xiaodong Xu

The band structure of many semiconducting monolayer transition metal dichalcogenides (TMDs) possesses two degenerate valleys, with equal and opposite Berry curvature. It has been predicted that, when illuminated with circularly polarized…

Mesoscale and Nanoscale Physics · Physics 2017-09-19 Nicolas Ubrig , Sanghyun Jo , Marc Philippi , Davide Costanzo , Helmuth Berger , Alexey B. Kuzmenko , Alberto F. Morpurgo

Semiconducting transition metal dichalcogenide monolayers have emerged as promising candidates for future valleytronics-based quantum information technologies. Two distinct momentum-states of tightly-bound electron-hole pairs in these…

Mesoscale and Nanoscale Physics · Physics 2017-03-16 Gerd Plechinger , Tobias Korn , John M. Lupton

While conventional semiconductor technology relies on the manipulation of electrical charge for the implementation of computational logic, additional degrees of freedom such as spin and valley offer alternative avenues for the encoding of…

We show that excitons and free carriers in K and K' valleys of transition metal dichalcogenide monolayers can be entangled with respect to their valley degree of freedom by absorbing linearly polarized single photons. This effect does not…

Mesoscale and Nanoscale Physics · Physics 2015-08-12 Mikhail Tokman , Yongrui Wang , Alexey Belyanin

We study the exciton states in the symmetrically biased dice model, the electronic structures of which have an isolated flat band between two dispersive bands. At 1/3 or 2/3 filling, the model describes a two-dimensional semiconductor with…

Mesoscale and Nanoscale Physics · Physics 2023-04-27 Lei Hao

Electrons in two-dimensional materials possess an additional quantum attribute, the valley pseudospin, labelled as $\mathbf{K}$ and $\mathbf{K}^{\prime}$ -- analogous to the spin up and spin down. The majority of research to achieve…

Optics · Physics 2023-06-06 Navdeep Rana , Gopal Dixit

Layered transition metal dichalcogenides (TMDCs) host a variety of strongly bound exciton complexes that control the optical properties in these materials. Apart from spin and valley, layer index provides an additional degree of freedom in…

Mesoscale and Nanoscale Physics · Physics 2019-05-08 Sarthak Das , Garima Gupta , Kausik Majumdar

A monolayer of a transition metal dichalcogenide (TMD) such as WSe$_2$ is a two-dimensional (2D) direct band-gap valley-semiconductor having an effective Honeycomb lattice structure with broken inversion symmetry. The inequivalent valleys…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Ajit Srivastava , Meinrad Sidler , Adrien V. Allain , Dominik S. Lembke , Andras Kis , Atac Imamoglu

Monolayer semiconductors, given their thickness at the atomic scale, present unique electrostatic environments due to the sharp interfaces between the semiconductor film and surrounding materials. These interfaces significantly impact both…

Mesoscale and Nanoscale Physics · Physics 2026-05-22 Kelly Y. Muñoz-Gómez , Hanz Y. Ramírez-Gómez

The monolayer transition metal dichalcogenides are an emergent semiconductor platform exhibiting rich excitonic physics with coupled spin-valley degree of freedom and optical addressability. Here, we report a new series of low energy…