Seminarium Fizyki Ciała Stałego
sala 0.06, ul. Pasteura 5
2019-04-12 (10:15) 
dr hab. Marek Potemski (Laboratoire National des Champs Magnétiques Intenses, Grenoble, France & Faculty of Physics, University of Warsaw, Poland)
Optical properties of atomically thin semiconductors
Atomically-thin layers of semiconducting transitions metal dichalcogenides (S-TMD) represent a new class of two-dimensional systems which are interesting from the viewpoint of their fundamental electronic properties (unusual band structure, unconventional excitons, valley selective circular polarization of optical transitions) and possible optoelectronic applications (light emitting- and photo-diodes).
A summary of our knowledge on optical response (excitonic resonances) and the related electronic bands of mono- and multi-layers of WSe2-, WS2-, MoSe2-, WS2- and MoTe2- and WS2-compounds will be presented. Particular emphasis will be focused on rich physics of excitons in S-TMD monolayers. Bright and dark excitonic ground states as well as their peculiar (non-hydrogen like) excitation spectra will be discussed in view of our magneto-optical studies and recent theoretical approaches. Moreover, the hybridization of electronic bands and the related fine structure of excitonic resonances in S-TMD multilayers will be examined.
Considerable attention will be focused on striking effects and unresolved problems which continue to stimulate the intense studies of S-TMD layers [1].
* In collaboration with M.R. Molas, A. Slobodeniuk, A. Arora, M. Koperski, C. Faugeras, K. Nogajewski, M. Bartos, K. Watanabe, T. Taniguchi, P. Kossacki,, Ł. Bala, A. Babinski, J. Wyzula, D. Vaclavkova.
[1] Optical properties of atomically thin transition metal dichalcogenides: Observations and puzzles, M. Koperski, M. R. Molas, A. Arora, K. Nogajewski, A. O. Slobodeniuk, C. Faugeras, and M. Potemski, Nanophotonics 6, 1289 (2017).(arXiv:1612.05879).
A summary of our knowledge on optical response (excitonic resonances) and the related electronic bands of mono- and multi-layers of WSe2-, WS2-, MoSe2-, WS2- and MoTe2- and WS2-compounds will be presented. Particular emphasis will be focused on rich physics of excitons in S-TMD monolayers. Bright and dark excitonic ground states as well as their peculiar (non-hydrogen like) excitation spectra will be discussed in view of our magneto-optical studies and recent theoretical approaches. Moreover, the hybridization of electronic bands and the related fine structure of excitonic resonances in S-TMD multilayers will be examined.
Considerable attention will be focused on striking effects and unresolved problems which continue to stimulate the intense studies of S-TMD layers [1].
* In collaboration with M.R. Molas, A. Slobodeniuk, A. Arora, M. Koperski, C. Faugeras, K. Nogajewski, M. Bartos, K. Watanabe, T. Taniguchi, P. Kossacki,, Ł. Bala, A. Babinski, J. Wyzula, D. Vaclavkova.
[1] Optical properties of atomically thin transition metal dichalcogenides: Observations and puzzles, M. Koperski, M. R. Molas, A. Arora, K. Nogajewski, A. O. Slobodeniuk, C. Faugeras, and M. Potemski, Nanophotonics 6, 1289 (2017).(arXiv:1612.05879).