Optical frequency combs have revolutionized optical frequency metrology in just a few years. They have made it possible to directly count light field oscillations of several 100 million million cycles per second and they have been recognized and honored by the highest distinction possible in science: The 2005 Nobel-Prize to T.W. Hansch (MPQ Germany) and J. Hall (JILA, USA). Measuring optical frequencies is not only of critical importance in fundamental science and atomic clocks but moreover is of increasing importance in technology. Frequency combs have enabled advances in other areas, such as gas sensing, Fourier transform spectroscopy or range-finding and astronomy. However a major obstacle has been the lack of integration; it has been impossible to create compact on chip comb sources.  The aim of this project is to build a planar optical frequency comb generator on a chip using CMOS compatible processing. 

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