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Related Experiment Video

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Towards spontaneous parametric down conversion from monolayer MoS₂.

Hatef Dinparasti Saleh¹, Stefano Vezzoli¹, Lucia Caspani^1,2

¹Institute of Photonics and Quantum Sciences, SUPA, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom.

Scientific Reports

|March 3, 2018

Summary

This summary is machine-generated.

We studied the nonlinear optical properties of 2D molybdenum disulfide (MoS₂) for spontaneous parametric down-conversion (SPDC). IR regime measurements indicate SPDC is possible, differing between single-layer and multi-layer MoS₂.

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Area of Science:

Materials Science
Quantum Optics
Photonics

Background:

Two-dimensional (2D) materials like molybdenum disulfide (MoS₂) exhibit unique optical nonlinearities.
Spontaneous parametric down-conversion (SPDC) is a key quantum optical process relying on optical nonlinearity.
Understanding nonlinearities in 2D materials is crucial for developing novel photonic devices.

Purpose of the Study:

To investigate the second-order optical nonlinearity of 2D MoS₂.
To assess the potential of MoS₂ for spontaneous parametric down-conversion (SPDC).
To differentiate SPDC signals from photoluminescence and characterize multilayer MoS₂ emissions.

Main Methods:

Theoretical modeling of SPDC in subwavelength nonlinear media.
Experimental measurements in both visible and infrared (IR) spectral regimes.
Polarization, power dependence, and lifetime measurements around 1560 nm.

Main Results:

A model for SPDC in subwavelength media was developed, relaxing phase-matching conditions.
Photoluminescence hindered visible SPDC detection; IR regime showed indications of SPDC.
Single-layer MoS₂ SPDC signals differed from multilayer MoS₂, which exhibited enhanced edge photoluminescence.

Conclusions:

2D MoS₂ shows potential for SPDC, particularly in the IR regime.
The nonlinear optical response is distinct between monolayer and multilayer MoS₂.
Multilayer MoS₂ exhibits unique edge-enhanced photoluminescence, distinct from SPDC.