Interplay of an anisotropy and orientational relaxation processes in luminescence and lasing of dyes

Bound state vector solitons with locked and precessing states of polarization

“…Here S 0 = const and α is determined by the ratio of linear to circular birefringence strength. In mode locked laser, in-cavity polarization controller contributes both into linear and circular birefringence whereas anisotropy induced by pump light is suppressed due to relaxation orientation caused by excitation migration [37,38]. Mode locked operation changes the active medium anisotropy (both linear and circular) due to polarization hole burning and so the pulse SOP located on a circle as shown in Fig.…”

“…The depth of the hole in orientation distribution of inversion is proportional to the laser power and so with periodical oscillations of the output power ( Fig. 5(c)) light induced anisotropy in an active medium will be periodically modulated [37,38]. If the round trip equals to the rational part of the beat length then SOP after few round trips will slightly deviate from the initial one and can reproduce itself for the period of pulse power oscillations only which is 400 round trips in our case ( Fig.…”

Polarisation Dynamics of Vector Soliton Molecules in Mode Locked Fibre Laser

“…The rate of excitation migration is very high in LIEKKI™ Er80-8/125 used herein due to the high concentration of erbium ions and so the anisotropy induced by pump light is supressed4647. Polarisation hole burning46474849 changes the active medium anisotropy (both linear and circular) and so pulse SOP is located on a circle as shown in Fig. 7 (a).…”

“…The depth of the hole in the orientational distribution of inversion is proportional to the laser power and so with periodic oscillations of the output power (Fig. 5 (b)) light induced anisotropy in an active medium will be periodically modulated46474849. In this case, if the round trip is equal to the one third of beat length then SOP after three round trips will deviate slightly from the initial one as shown in Figs.…”

“…Unlike polarisation dynamics of vector solitons on the Poincaré sphere demonstrated by Akhmediev, Soto-Crespo26 and Komarov et al45, we study experimentally how polarisation hole burning in an active medium46474849 contributes to the polarisation dynamics. All results are obtained based on inline polarimeter (OFS TruePhase IPLM) optimised for high-speed operation505152.…”