Related Experiment Video
Updated: Dec 14, 2025
11:30
Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
12.0K
Highly nonlinear trion-polaritons in a monolayer semiconductor.
R P A Emmanuele1, M Sich1, O Kyriienko2,3
1Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.
Nature Communications
|July 19, 2020
Summary
Semiconducting transition metal dichalcogenides (TMDCs) enable strong nonlinear optical effects for quantum signal processing. Researchers achieved this using charged excitons (trions) in MoSe2, leading to scalable quantum optics applications.
Area of Science:
- Quantum Optics
- Materials Science
- Condensed Matter Physics
Background:
- Ultrafast and quantum optical signal processing requires highly nonlinear optical materials with strong photon-photon interactions.
- Semiconducting transition metal dichalcogenides (TMDCs) are promising candidates for such applications.
Purpose of the Study:
- To investigate strong Kerr-like nonlinearities in TMDCs by utilizing charged excitons (trions).
- To explore the potential of trion-polaritons in monolayer MoSe2 for optical signal processing.
Main Methods:
- Hybridization of trions in monolayer MoSe2 with a microcavity mode at low electron densities.
- Observation and characterization of trion-polaritons and their nonlinear optical properties.
- Theoretical modeling accounting for the composite nature and statistics of excitons and trions.
Main Results:
- Realization of trion-polaritons exhibiting significant energy shifts at low photon fluxes due to phase space filling.
- Trion-to-neutral exciton-polariton interaction strength ratio found to be 10-100 in TMDC materials.
- Trion-polariton nonlinearity demonstrated to be comparable to other polariton systems.
Conclusions:
- Strong nonlinearities achieved using trions in TMDCs pave the way for advanced optical signal processing.
- The findings support theoretical models of composite particle statistics.
- This work enables scalable quantum optics applications using TMDCs.
More Related Videos
Related Concept Videos
01:22Semiconductors
1.2K
There is variation in the electrical conductivity of materials - metals, semiconductors, and insulators that are showcased with the help of the energy band diagrams.
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
1.2K
01:20Types of Semiconductors
1.2K
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
1.2K
01:27Biasing of Metal-Semiconductor Junctions
466
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
466
01:22Carrier Generation and Recombination
1.1K
Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
1.1K
01:16Biasing of P-N Junction
1.5K
The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
1.5K
01:11P-N junction
980
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
980