English
Related papers

Related papers: Enabling valley selective exciton scattering in mo…

200 papers

Electrons and holes can spontaneously form excitons and condense in a semimetal or semiconductor, as predicted decades ago. This type of Bose condensation can happen at much higher temperatures in comparison with dilute atomic gases.…

Mesoscale and Nanoscale Physics · Physics 2023-02-24 Qiang Gao , Yang-hao Chan , Yuzhe Wang , Haotian Zhang , Jinxu Pu , Shengtao Cui , Yichen Yang , Zhengtai Liu , Dawei Shen , Zhe Sun , Juan Jiang , Tai C. Chiang , Peng Chen

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

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…

Moir\'e superlattices created by stacking atomic layers of transition metal dichalcogenide semiconductors have emerged as a class of fascinating artificial photonic and electronic materials. An appealing attribute of these structures is the…

Mesoscale and Nanoscale Physics · Physics 2025-03-11 Yueh-Chun Wu , Matthew DeCapua , ZhongChen Xu , Takashi Taniguchi , Kenji Watanabe , YouGuo Shi , Jun Yan

Spatially indirect excitons with displaced wavefunctions of electrons and holes play a pivotal role in a large portfolio of fascinating physical phenomena and emerging optoelectronic applications, such as valleytronics, exciton spin Hall…

Heterobilayers consisting of MoSe$_2$ and WSe$_2$ monolayers can host optically bright interlayer excitons with intriguing properties such as ultralong lifetimes and pronounced circular polarization of their photoluminescence due to valley…

Mesoscale and Nanoscale Physics · Physics 2022-05-09 D. S. Smirnov , J. Holler , M. Kempf , J. Zipfel , P. Nagler , M. V. Ballottin , A. A. Mitioglu , A. Chernikov , P. C. M. Christianen , C. Schüller , T. Korn

The direct gap interband transitions in transition metal dichalcogenides monolayers are governed by chiral optical selection rules. Determined by laser helicity, optical transitions in either the $K^+$ or $K^-$ valley in momentum space are…

Mesoscale and Nanoscale Physics · Physics 2016-10-26 G. Wang , X. Marie , B. L. Liu , T. Amand , C. Robert , F. Cadiz , P. Renucci , B. Urbaszek

In monolayer transition-metal dichalcogenide semiconductors, many-body correlations can manifest in optical spectra when photoexcited electron-hole pairs (excitons) are introduced into a 2D Fermi sea of mobile carriers. At low carrier…

Mesoscale and Nanoscale Physics · Physics 2022-01-04 Jing Li , Mateusz Goryca , Junho Choi , Xiaodong Xu , Scott A. Crooker

Monolayers of transition metal dichalcogenides (TMDCs) feature exceptional optical properties that are dominated by excitons, tightly bound electron-hole pairs. Forming van der Waals heterostructures by deterministically stacking individual…

The bound electron-hole pairs known as excitons govern the optical properties of insulating solids. While their behavior in equilibrium is well-understood theoretically, the nonequilibrium regime at high excitation densities-where phenomena…

Mesoscale and Nanoscale Physics · Physics 2025-10-31 Pushpendra Yadav

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By…

By pumping nonresonantly a MoS$_2$ monolayer at $13$ K under a circularly polarized cw laser, we observe exciton energy redshifts that break the degeneracy between B excitons with opposite spin. The energy splitting increases monotonically…

Mesoscale and Nanoscale Physics · Physics 2020-01-07 Yao Li , G. Li , Xiaokun Zhai , Shi Fu Xiong , Hongjun Liu , Xiao Wang , Haitao Chen , Ying Gao , Xiu Zhang , Tong Liu , Yuan Ren , Xuekai Ma , Hongbin Fu , T. Gao

In monolayer transition metal dichalcogenides, tightly bound excitons have been discovered with a valley pseudospin that can be optically addressed through polarization selection rules. Here, we show that this valley pseudospin is strongly…

Mesoscale and Nanoscale Physics · Physics 2014-05-20 Hongyi Yu , Guibin Liu , Pu Gong , Xiaodong Xu , Wang Yao

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…

Two-dimensional (2D) van-der-Waals materials are a promising platform for exciton state engineering. In this paper, we study the properties of excitons in 2D group VI transition-metal dichalcogenide (TMD) semiconductors that are modified by…

Strongly Correlated Electrons · Physics 2026-05-08 Jose M. Torres-Lopez , Sudipta Kundu , Felipe H. da Jornada , Tony Heinz , Allan H. MacDonald

In twisted homobilayer transition metal dichalcogenides, intra- and inter-layer valley excitons hybridize with the layer configurations spatially varying in the moir\'e. The ground state valley excitons are trapped at two high-symmetry…

Mesoscale and Nanoscale Physics · Physics 2021-05-27 Hongyi Yu , Wang Yao

Condensation of bosons into a macroscopic quantum state belongs to the most intriguing phenomena in nature. It was first realized in quantum gases of ultra-cold atoms, but more recently became accessible in open-dissipative, exciton-based…

Excitons -- elementary excitations formed by bound electron-hole pairs -- govern the optical properties and excited-state dynamics of materials. In two-dimensions (2D), excitons are theoretically predicted to have a linear energy-momentum…

Materials Science · Physics 2025-03-14 Luna Y. Liu , Steffi Y. Woo , Jinyuan Wu , Bowen Hou , Cong Su , Diana Y. Qiu

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

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