1. |
- Fang, Hanlin, 1992, et al.
(author)
-
Localization and interaction of interlayer excitons in MoSe 2 /WSe 2 heterobilayers
- 2023
-
In: Nature Communications. - 2041-1723 .- 2041-1723. ; 14:1
-
Journal article (peer-reviewed)abstract
- Transition metal dichalcogenide (TMD) heterobilayers provide a versatile platform to explore unique excitonic physics via the properties of the constituent TMDs and external stimuli. Interlayer excitons (IXs) can form in TMD heterobilayers as delocalized or localized states. However, the localization of IX in different types of potential traps, the emergence of biexcitons in the high-excitation regime, and the impact of potential traps on biexciton formation have remained elusive. In our work, we observe two types of potential traps in a MoSe2/WSe2 heterobilayer, which result in significantly different emission behavior of IXs at different temperatures. We identify the origin of these traps as localized defect states and the moiré potential of the TMD heterobilayer. Furthermore, with strong excitation intensity, a superlinear emission behavior indicates the emergence of interlayer biexcitons, whose formation peaks at a specific temperature. Our work elucidates the different excitation and temperature regimes required for the formation of both localized and delocalized IX and biexcitons and, thus, contributes to a better understanding and application of the rich exciton physics in TMD heterostructures.
|
|
2. |
- Generalov, Andrey, 1987, et al.
(author)
-
Distinction of the thermoelectric effect in graphene FET THz detectors
- 2020
-
In: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. ; 2020-November, s. 504-505
-
Conference paper (peer-reviewed)abstract
- This work presents an approach to distinguish the thermoelectric detection mechanism from the resistive mixing or plasma wave rectification in graphene FET THz detectors. Numerical full-wave simulations validate the asymmetric feeding of the existing antenna design and allow for comparison with a reference design of thermoelectric detectors. The experimental results verify quantitively the thermoelectric contribution to the overall rectification, which allows for more accurate modelling of the GFET THz detectors.
|
|
3. |
- Lin, Qiaoling, et al.
(author)
-
Interlayer Exciton Lasing in Atomically Thin Heterostructures
- 2023
-
In: International Conference on Metamaterials, Photonic Crystals and Plasmonics. - 2429-1390. ; , s. 1691-
-
Conference paper (peer-reviewed)abstract
- We present an interlayer exciton laser composed of a MoS2/WSe2 heterostructure integrated with a silicon photonic topological microcavity with a quality factor of up to 104. We achieve excitonic lasing with ultra-low threshold, high side-mode suppression ratio and the longest emission wavelength to the telecommunication O-band.
|
|
4. |
- Wang, Yuchen, et al.
(author)
-
Enhancing Si3N4 Waveguide Nonlinearity with Heterogeneous Integration of Few-Layer WS2
- 2021
-
In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 8:9, s. 2713-2721
-
Journal article (peer-reviewed)abstract
- The heterogeneous integration of low-dimensional materials with photonic waveguides has spurred wide research interest. Here, we report on the experimental investigation and the numerical modeling of enhanced nonlinear pulse broadening in silicon nitride waveguides with the heterogeneous integration of few-layer WS2. After transferring a few-layer WS2 flake of similar to 14.8 mu m length, the pulse spectral broadening in a dispersion-engineered silicon nitride waveguide has been enhanced by similar to 48.8% in bandwidth. Through numerical modeling, an effective nonlinear coefficient higher than 600 m(-1) W-1 has been retrieved for the heterogeneous waveguide indicating an enhancement factor of larger than 300 with respect to the pristine waveguide at a wavelength of 800 nm. With further advances in two-dimensional material fabrication and integration techniques, on-chip heterostructures will offer another degree of freedom for waveguide engineering, enabling high-performance nonlinear optical devices, such as frequency combs and quantum light sources.
|
|
5. |
- Wang, Yuchen, et al.
(author)
-
Heterogeneous silicon nitride waveguide integrated with few-layer WS2 for on-chip nonlinear optics
- 2021
-
In: 2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC). - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- Recently, two-dimensional materials have attracted significant interests for nonlinear optics [1] . Here, we report on the experimental investigation and the numerical modelling of nonlinear pulse propagation in a heterogeneous silicon nitride channel waveguide with the integration of a few-layer WS 2 flake significantly increasing the effective nonlinearity.
|
|