Submitted manuscript, 948 KB, PDF document
Rights statement: © 2015 American Physical Society
Final published version, 748 KB, PDF document
Available under license: CC BY-NC: Creative Commons Attribution-NonCommercial 4.0 International License
Research output: Contribution to Journal/Magazine › Journal article › peer-review
| Article number | 037401 |
|---|---|
| <mark>Journal publication date</mark> | 22/01/2015 |
| <mark>Journal</mark> | Physical review letters |
| Issue number | 3 |
| Volume | 114 |
| Number of pages | 5 |
| Publication Status | Published |
| <mark>Original language</mark> | English |
Using polarization-resolved photoluminescence spectroscopy, we investigate the breaking of valley degeneracy by an out-of-plane magnetic field in back-gated monolayer MoSe2 devices. We observe a linear splitting of -0.22 meV/T between luminescence peak energies in sigma(+) and sigma(-) emission for both neutral and charged excitons. The optical selection rules of monolayer MoSe2 couple the photon handedness to the exciton valley degree of freedom; so this splitting demonstrates valley degeneracy breaking. In addition, we find that the luminescence handedness can be controlled with a magnetic field to a degree that depends on the back-gate voltage. An applied magnetic field, therefore, provides effective strategies for control over the valley degree of freedom.