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Related papers: Valley-Polarized Exciton Dynamics in Exfoliated Mo…

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Coupling between exciton states across the Brillouin zone in monolayer transition metal dichalcogenides can lead to ultrafast valley depolarization. Using time- and angle-resolved photoemission, we present momentum- and energy-resolved…

The lowest energy states in transition metal dichalcogenide (TMD) monolayers follow valley selection rules, which have attracted vast interest due to the possibility of encoding and processing of quantum information. However, these quantum…

Mesoscale and Nanoscale Physics · Physics 2024-03-22 Sergii Morozov , Torgom Yezekyan , Christian Wolff , Sergey I. Bozhevolnyi , N. Asger Mortensen

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

Monolayer transition metal dichalcogenides have emerged as prominent candidates to explore the complex interplay between the spin and the valleys degrees of freedom. The strong spin-orbit interaction and broken inversion symmetry within…

Transition metal dichalcogenide monolayers are highly interesting for potential valleytronic applications due to the coupling of spin and valley degrees of freedom and valley-selective excitonic transitions. However, ultrafast recombination…

Mesoscale and Nanoscale Physics · Physics 2017-09-05 Markus Schwemmer , Philipp Nagler , Andreas Hanninger , Christian Schüller , Tobias Korn

The presence of two spin-split valleys in monolayer (1L) transition metal dichalcogenide (TMD) semiconductors supports versatile exciton species classified by their spin and valley quantum numbers. While the spin-0 intravalley exciton,…

Mesoscale and Nanoscale Physics · Physics 2020-07-22 Yueh-Chun Wu , Sarath Samudrala , Andrew McClung , Takashi Taniguchi , Kenji Watanabe , Amir Arbabi , Jun Yan

Monolayer transition metal dichalcogenides are a promising platform to investigate many-body interactions of excitonic complexes. In monolayer tungsten diselenide, the ground-state exciton is dark (spin-indirect), and the valley degeneracy…

The ability to monitor and control distinct states is at the heart of emerging quantum technologies. The valley pseudospin in transition metal dichalcogenide (TMDC) monolayers is a promising degree of freedom for such control, with the…

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

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…

One of the main tasks in the investigation of 2-dimensional transition metal dichalcogenides is the determination of valley lifetimes. In this work, we combine time-resolved Kerr rotation with electrical transport measurements to explore…

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 doped transition metal dichalcogenides, optically created excitons (bound electron-hole pairs) can strongly interact with a Fermi sea of electrons to form Fermi polaron quasiparticles. When there are two distinct Fermi seas, as is the…

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

Manipulating the valley degree of freedom to encode information for potential valleytronic devices has ignited a new direction in solid-state physics. A significant, fundamental challenge in the field of valleytronics is how to generate and…

Mesoscale and Nanoscale Physics · Physics 2020-07-02 Hui-Ying Mu , Yi-Tong Yao , Jie-Ru Li , Guo-Cai Liu , Chao He , Ying-Jie Sun , Guang Yang , Xing-Tao An , Yong-Zhe Zhang , Jian-Jun Liu

In monolayer transition metal dichalcogenides time-reversal symmetry, combined with space-inversion symmetry, defines the spin-valley degree of freedom. As such, engineering and control of time-reversal symmetry by optical or magnetic…

Selective control over the emission pattern of valley-polarized excitons in monolayer transition metal dichalcogenides is crucial for developing novel valleytronic, quantum information, and optoelectronic devices. While significant progress…

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…

Optical spectroscopy in high magnetic fields $B\leq65$ T is used to reveal the very different nature of carriers in monolayer and bulk transition metal dichalcogenides. In monolayer WSe$_{2}$, the exciton emission shifts linearly with the…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 A. A. Mitioglu , P. Plochocka , Á. Granados del Aguila , P. C. M. Christianen , G. Deligeorgis , S. Anghel , L. Kulyuk , D. K. Maude

A rate equation model for the dark and bright excitons kinetics is proposed which explains the wide variation in the observed degree of circular polarization of the PL emission in different TMDs monolayers. Our work suggests that the dark…

Mesoscale and Nanoscale Physics · Physics 2017-01-18 M. Baranowski , A. Surrente , D. K. Maude , M Ballottin , A. A. Mitioglu , P. C. M. Christianen , Y. C. Kung , D. Dumcenco , A. Kis , P Plochocka