Non-linear micro-ring resonators

为了真正便携，必须使用毫瓦激光泵浦功率产生光频梳。商业系统使用几个100 pJ的脉冲和复杂的干涉稳定，有时与放大级：这需要发展的微梳的基础上有效的超非线性光波导微谐振器，表现出克尔效应。五氧化二钽波导系统：我们的方法涉及使用非常规材料。我们将在内部采用CMOS兼容工艺制造五氧化二钽通道波导。这种材料的x（3）非线性约为氮化硅的3倍，具有类似的高折射率，并且我们已经证明了低于0.2 dB/cm的低损耗波导。波导的几何形状是硅上二氧化硅顶部的五氧化二钽，可以封装在二氧化硅或氧化铝层中;这种配置足够灵活，可以定制色散曲线。我们的主要目标是设计色散和降低波导系统的损耗。我们将设计高Q值微环波导的色散，以实现从CW源在1和2.1 μ m之间的波长范围内的单孤子传输。波导系统将使用我们自己研制的半导体量子阱激光器进行泵浦。

To be truly portable, an optical frequency comb must be generated using milliwatts of laser pump power. Commercial systems use few-100pJ pulses and complicated interferometric stabilization sometimes with amplified stages: this calls for the development of micro-combs based on efficient ultra-nonlinear optical waveguide micro-resonators that exhibit the Kerr effect. Tantalum Pentoxide waveguide system: Our approach involves use of an unconventional material. We shall fabricate tantalum pentoxide channel waveguides in-house, in a CMOS-compatible process. This material has a x(3) nonlinearity about 3x that of silicon nitride, a similarly high refractive index and we have demonstrated already low loss waveguides below 0.2 dB/cm. The waveguide geometry is tantalum pentoxide on top of silica on silicon which can be encapsulated in a silica or alumina layer; this configuration is flexible enough to allow customized dispersion profiles. Our main target shall be to engineer the dispersion and lower the losses of the waveguide system. We will design the dispersion of the high-Q micro-ring waveguides to achieve single soliton propagation from CW sources at the wavelength range between 1 and 2.1 um. The waveguide system will be pumped using our home-grown semiconductor quantum well lasers.