Robust optical emission polarization in MoS2 monolayers through selective valley excitation

@article{Sallen2012RobustOE,
  title={Robust optical emission polarization in MoS2 monolayers through selective valley excitation},
  author={G. Sallen and L. Bouet and X. Marie and Gang Wang and C. Zhu and W. Han and Y. Lu and P. Tan and T. Amand and Baoli Liu and B. Urbaszek},
  journal={Physical Review B},
  year={2012},
  volume={86},
  pages={081301}
}
We report polarization resolved photoluminescence from monolayer MoS2, a two-dimensional, noncentrosymmetric crystal with direct energy gaps at two different valleys in momentum space. The inherent chiral optical selectivity allows exciting one of these valleys, and close to 90% polarized emission at 4 K is observed with 40% polarization remaining at 300 K. The high polarization degree of the emission remains unchanged in transverse magnetic fields up to 9 T indicating robust, selective valley… Expand

Figures from this paper

High room temperature optical polarization due to spin-valley coupling in monolayer WS2
We prepare single-layer WS2 films such that the photoluminescence is from either the neutral exciton or the negatively charged trion. While the neutral exciton emission has zero polarization at roomExpand
Breaking of valley degeneracy by magnetic field in monolayer MoSe2.
TLDR
Using polarization-resolved photoluminescence spectroscopy, the breaking of valley degeneracy by an out-of-plane magnetic field in back-gated monolayer MoSe2 devices is investigated and the luminescence handedness can be controlled with a magnetic field to a degree that depends on the back-gate voltage. Expand
Polarization and time-resolved photoluminescence spectroscopy of excitons in MoSe2 monolayers
We investigate valley exciton dynamics in MoSe2 monolayers in polarization- and time-resolved photoluminescence (PL) spectroscopy at 4 K. Following circularly polarized laser excitation, we record aExpand
Valley polarization and intervalley scattering in monolayer MoS$_{2}$
We probe the degree of circular polarization of the emitted photoluminescence from a single layer of MoS2 as a function of the circularly polarized photo-excitation energy. A Single layer of MoS2 hasExpand
Valley dynamics probed through charged and neutral exciton emission in monolayer WSe2
Optical interband transitions in monolayer transition metal dichalcogenides such as WSe2 and MoS2 are governed by chiral selection rules. This allows efficient optical initialization of an electronExpand
Valley and spin dynamics in MoSe2 two-dimensional crystals.
TLDR
A valley relaxation time of 9 ± 3 ps at room temperature is obtained, which is at least one order of magnitude shorter than the simultaneously measured exciton lifetime. Expand
Optical generation of excitonic valley coherence
devices, we first establish the circularly polarizedoptical selection rules for addressing individual valley excitonsand trions. We then demonstrate coherence between valleyexcitons through theExpand
Valley splitting and polarization by the Zeeman effect in monolayer MoSe2.
TLDR
This work has measured circularly polarized photoluminescence in monolayer MoSe2 under perpendicular magnetic fields up to 10 T and the magnitude of the Zeeman shift agrees with predicted magnetic moments for carriers in the conduction and valence bands. Expand
Valley Polarization in Transition-Metal Dichalcogenides by Optical Pumping
Degenerate valleys of energy bands well separated in momentum space constitute a discrete degrees of freedom for low-energy electrons. This has led to the emergence of valleytronics, a conceptualExpand
Valley-Polarized Exciton Dynamics in Exfoliated Monolayer WSe2
Semiconducting transition-metal dichalcogenide monolayers have emerged as promising candidates for future valleytronics-based quantum information technologies. Two distinct momentum states of tightlyExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 22 REFERENCES
Springer Series in Solid-State Sciences
A semiconductor flip flop capable of operating before, during and after an ionizing radiation environment. The radiation hardening is achieved by use of a capacitive memory in the cross coupledExpand
Nature
  • R. Rosenfeld
  • Medicine
  • Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery
  • 2009
TLDR
I am writing with a simple plea to balance the voluminous articles about treatment in your journal with a modicum of information about nature and caring effects to rekindle the perception of physicians as healers, not only treaters, who relish the gifts of nature, and foster the humanistic aspect of medicine that has thrived for millennia. Expand
Nature Nanotech
  • DOI: 10.1038/NNANO.2012.95
  • 2012
Nature Nanotech
  • DOI: 10.1038/NNANO.2012.96
  • 2012
Applied Physics Letters 99
  • 102109
  • 2011
(b)
Phys
  • Rev. B 85, 205302
  • 2012
Phys
  • 5 Rev. Lett. 108, 196802
  • 2012
phys
  • stat. sol. (RRL) 6, 126
  • 2012
Nano Letters 11
  • 5111
  • 2011
...
1
2
3
...