Positive (>0 dB) Wavelength Conversion Efficiency in Temperature-Tuned Five-Segment Highly-Nonlinear Fiber Without Pump Dithering

By temperature tuning, we align zero-dispersion wavelengths of several fiber segments while detuning their Brillouin frequencies. Despite 2.5-fold fiber length increase, we obtain 2-dB higher Brillouin threshold, enabling >0 dB conversion efficiency without pump modulation.