The generation and manipulation of entangled photons is one key challenge in the field of quantum technology. At present, entangled photons are commonly generated with nonlinear optical crystals, but such sources are typically bulky and require careful stabilization. 

Recently, ultra-thin nanostructures, so-called metasurfaces, have emerged as compact and stable sources of entangled photons. In addition to established semiconductor compounds, layered two-dimensional (2D) materials are becoming more and more interesting as metasurface starting material due to their strong nonlinearity, large refractive index, and rich symmetry properties. However, only a few candidates have been thoroughly investigated to date. 

In the first, hands-on part of this project, you will explore selected promising 2D materials. You will manually fabricate thin-film samples from bulk crystals and characterize their (nonlinear) optical properties. 

In the second part of the project you will use your measured data and the extracted material parameters to simulate nanostructures based on 2D materials with sub-wavelength thickness for quantum light generation and evaluate their photon entanglement properties. 

Through this project, you will develop skills in the area(s) of:

• The manual fabrication process of 2D material flakes for fundamental studies.
• Different characterization methods (Photoluminescence, Raman, AFM, Ellipsometry…).
• Experimental investigation of nonlinear optical properties of novel 2D materials.
• Simulation of potential candidates for quantum light generation. 

Knowledge in the fields of (nonlinear) optics, quantum mechanics, and solid-state physics is advantageous.