Extended Data Fig. 7: Analysis of the relative refractive index variation in the amplifier cavity.

Here we show the relative refractive index variation of the amplifier under operating conditions calculated as δn_bn_b⁻¹ = −δF F⁻¹ - δL_bL_b⁻¹. a, Relative change of the refractive index for the soliton states obtained across the mapped values, extracted from the free-spectral range variation of the ‘State Diagram 1’. The colour code in the map follows the inset showing the refractive index change. b, Same as panel a for the ‘State Diagram 2’.