Nonlinear & Microstructured Optical Materials

The Nonlinear & Microstructured Optical Materials Group is led by Professor Rob Eason.

The lithium niobate activity is led by Dr Sakellaris Mailis

Our mission is to identify and develop methods for the full utilization of the useful physical and optical properties of lithium niobate, a very gifted nonlinear optical ferroelectric crystal with a large presence in the photonics industry.

An important goal is to develop a complete material-processing toolbox which will enable the fabrication of complex multifunctional devices based on lithium niobate.

More specifically we strive to develop and understand the physics behind methods for:

• Ferroelectric domain engineering
• Direct writing of refractive and diffractive structures
• Surface and bulk micro-structuring

We are using a wide range of standard clean-room based micro-fabrication methods such as photolithography, ion beam milling, reactive ion etching, chemical etching, and deposition to non standard methods such as light assisted/induced ferroelectric domain inversion direct writing, inhibition of poling and preferential surface melting to gain control over the fabrication of useful combinations of domain engineered and microstructured arrangements on single crystal substrates that can be used to achieve multifunctional operation. 

Our experience and practice range from material science through to photonics ensuring fast and substantial two way feedback from the characterization to fabrication level.

• All optical laser induced ferroelectric domain inversion
• Light assisted poling
• UV laser induced poling inhibition
• Fabrication of single crystal micro-cantilevers
• Ultra-smooth single crystal photonic micro-structures
• Direct UV writing of optical waveguides in lithium niobate
• UV laser induced super hydrophilic surfaces in lithium niobate

• Nonlinear optical micro-resonators: (Sakellaris Mailis)

• Fabrication and characterization of micro-fabricated ultrasmooth whispering gallery mode resonators for the development of high Q passive and active nonlinear optical cavities for sensing applications
• Integrated quasi phase matched nonlinear microresonators based on ring and disc domain engineered lithium niobate waveguide superstructures

• Tailoring of refractive index profiles in optical waveguides by averaging distinct refractive index components on planar waveguide geometry thus breaking the continuous channel waveguide convention. For this task we use a fabrication tool based on a spatially selective laser printing method for rapid prototyping of 2D optical circuits. (Sakellaris Mailis and Robert W. Eason)
• Fabrication and characterization of lab-on-a-chip type of devices based on micro-structured opto-fluidic lithium niobate structures for biochemical applications (Sakellaris Mailis and Collin Sones)
• Development of scanning probe electric field sensors based on electro-optic, piezoelectric lithium niobate micro-structured tips (Sakellaris Mailis)

Research funding is provided by:

• EPSRC Portfolio Partnership in Photonics (grant reference EP/C515668/1)
• EU STREP "3D-DEMO" www.3d-demo.org/

GR/S47373/01 Light-induced domain engineering in ferroclectrics: a route to sub-micron poling

GR/S09999/01 Single-step UV direct-writing of channel waveguides in lithium niobate and lithium tantalate single crystals

GR/R46663/01 Feasibility study of focussed ion beam (FIB) direct write for micro-photonic applications

GR/R47295/01 Light-induced frustrated etching (LIFE) studies in LiNbO₃: latency effects and periodic micro-structuring

GR/N00302/01 ROPA: Microstructured LiNbO₃: Applications to MEMS technology

To search for a full list of our publications visit our publications database

• University of Bonn http://lxsa.physik.uni-bonn.de/hertz/index_e.html
• Technical University of Athens http://www.ntua.gr/en_index.htm
• National Hellenic Research Foundation http://www.eie.gr/
• EPFL http://www.epfl.ch/
• CNRS-FEMTO http://www.femto-st.fr/
• ABCD Technology http://www.abcd-technology.com/
• SAFC http://www.sigmaaldrich.com/safc-global/en-us/home.html
• Saes Getters http://www.saesgetters.com/
• INFLPR http://www.inflpr.ro/

The FAST Lab

The FAST Lab (Femtosecond Applications of Science & Technology) is a multi-user facility that hosts several projects from this group more...