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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Spin-valley Rashba monolayer laser
Kexiu Rong1, Xiaoyang Duan1, Bo Wang2
1Atomic-Scale Photonics Laboratory, Russell Berrie Nanotechnology Institute, and Helen Diller Quantum Center, Technion - Israel Institute of Technology, Haifa, Israel.
Nature Materials
|July 6, 2023
Summary
Researchers developed a novel spin-optical laser using a tungsten disulfide (WS₂) monolayer. This atomic-scale light source demonstrates robust spin polarization and coherence at room temperature, paving the way for advanced optical technologies.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Optoelectronics
Background:
- Direct-bandgap transition metal dichalcogenide monolayers exhibit valley-contrasting optical selection rules, making them promising for spin-optical applications.
- Atomic-scale light sources are crucial for next-generation optoelectronic devices.
Purpose of the Study:
- To demonstrate a spin-optical monolayer laser utilizing a WS₂ monolayer integrated into a microcavity.
- To investigate the generation and properties of photonic spin-valley resonances.
Main Methods:
- Incorporation of a WS₂ monolayer into a heterostructure microcavity.
- Generation of spin-valley modes via photonic Rashba-type spin splitting of a bound state in the continuum.
- Utilizing inversion symmetry breaking to induce photonic spin-orbit interaction.
Main Results:
- Demonstration of a functional spin-optical monolayer laser with intrinsic spin polarizations.
- Observation of high spatial and temporal coherence in the laser output.
- Achieved valley coherence in the WS₂ monolayer under arbitrary pump polarizations at room temperature.
- Exhibited symmetry-enabled robustness features.
Conclusions:
- The developed monolayer laser integrates electron and photon spins for coherent light generation.
- Monolayer-integrated spin-valley microcavities offer new possibilities for classical and non-classical spin-optical light sources.
- This work advances the development of atomic-scale, coherent spin-optical devices.
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