Report
The temperature influence on the brightening of neutral and charged dark excitons in WSe$_2$ monolayer
| العنوان: | The temperature influence on the brightening of neutral and charged dark excitons in WSe$_2$ monolayer |
|---|---|
| المؤلفون: | Kipczak, Ł., Zawadzka, N., Jana, D., Antoniazzi, I., Grzeszczyk, M., Zinkiewicz, M., Watanabe, K., Taniguchi, T., Potemski, M., Faugeras, C., Babiński, A., Molas, M. R. |
| سنة النشر: | 2024 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Mesoscale and Nanoscale Physics |
| الوصف: | The optically dark states play an important role in the electronic and optical properties of monolayers (MLs) of semiconducting transition metal dichalcogenides. The effect of temperature on the in-plane-field activation of the neutral and charged dark excitons is investigated in a WSe$_2$ ML encapsulated in hexagonal BN flakes. The brightening rates of the neutral dark (X$^D$) and grey (X$^G$) excitons and the negative dark trion (T$^D$) differ substantially at a particular temperature. More importantly, they vanish considerably by about 3 -- 4 orders of magnitude with the temperature increased from 4.2 K to 100 K. The quenching of the dark-related emissions is accompanied by the two-order-of-magnitude increase in the emissions of their neutral bright counterparts, $i.e.$ neutral bright exciton (X$^B$) and spin-singlet (T$^S$) and spin-triplet (T$^T$) negative trions, due to the thermal activations of dark states. Furthermore, the energy splittings between the dark X$^D$ and T$^D$ complexes and the corresponding bright X$^B$, T$^S$, and T$^T$ ones vary with temperature rises from 4.2 K to 100 K. This can be explained in terms of the different exciton-phonon couplings for the bright and dark excitons stemming from their distinct symmetry properties. Comment: Main text: 6 pages, 4 figures. Supplementary: 5 pages, 4 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2407.18117 |
| رقم الانضمام: | edsarx.2407.18117 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |