Quantum Optical Components

Laser-based processing methods can generate structures and build component groups used in the field of integrated quantum photonics, for example, for quantum computers, internet or metrology.

Compared to mechanical or lithographic processes, laser radiation has the benefit of flexible and fast processing without contacting the workpiece. In addition, it can selectively process the surfaces or the material volume of various materials – such as diamond, silicon carbide, gallium arsenide or lithium niobate – at a spatial precision of less than one micrometer. 

Fraunhofer ILT is developing technologies that make it possible to couple qubits photonically. For this, microscopically dimensioned interconnecting structures between the qubits have to be generated. Communication can take place via waveguiding structures integrated into semiconductors by means of local refractive index changes using ultrafast laser radiation. In addition to realizing targeted communication, this also allows for better collection of light emitted from qubits.

One focal point of Fraunhofer ILT’s research is developing surface and integrated structures based on lithium niobate for quantum optical circuits, so-called quantum gates for quantum computers. Elementary components are waveguides with structure sizes of a few micrometers. By using ultrafast laser radiation, the institute can generate corresponding individualized structures directly and at high precision. For optimized photon guidance properties, the surface roughness, in particular, is minimized so that the scattering effects play a negligible role in guiding visible or infrared light and costly post-processing steps can be eliminated.

In addition to micro and nano structuring with ultrafast lasers, selective laser-induced etching (SLE) is used to develop components such as waveguides, gratings, couplers and filters for new applications based on quantum technology.

Our services cover a wide range of topics. Related topics to quantum optical components and further research and development focuses can be found under the following links.