Fig. 4: Device yields vis-à-vis tunability of target three-wave mixing process.
a Thermo-optic tuning of a device’s SH spectrum up to \(\Delta {T}_{\max }=12{0}\,{{{\rm{K}}}}\) above room temperature using an off-chip ceramic heater (b, inset). The measured SH spectrum maintains approximately the same shape over the tuning range. b λSH red-shifts linearly with temperature within the range measured, with a thermo-optic tuning rate of 0.10 nm ⋅ K−1. c Yield on devices with operating wavelengths within thermo-optic tuning range of λ0 as a function of the maximum achievable temperature for measured distributions in Fig. 3e. d Tuning of device operating wavelength via deposition of thin layers of cladding oxide, \({d}_{{{{{\rm{SiO}}}}}_{2}}\)(e, inset). At large cladding thicknesses, widths of the SH spectra decrease as operating wavelengths are blue-shifted, indicating increasing group velocity mismatch between the fundamental and second harmonic of the quasi-phase matched process (upper panel); the impact of this is minor, however, for the small amounts of wavelength trimming (<50 nm) necessary in most cases. e Experimental data showing >100 nm blue-shift of the operating wavelength observed, with the rate of blue-shift decreasing as more silica cladding is deposited.
