ABSTRACT: The polarization properties of an evanescent-wave pumped Whispering Gallery Mode (WGM) fibre laser have been investigated.
It is found that there are two kinds of polarization lasing beam emitting from the evanescent-wave pumped WGM fibre laser
under two different pump conditions. When the pump beam is strictly along the axial direction of an optical fibre, the lasing
emission is transverse electric wave and the electrical vectors at emitting points are along the radial direction of the fibre,
which forms a special radial polarization radiation. However, when the pump beam deviates from the axial direction of the
fibre, both transverse electric and transverse magnetic waves exist in the lasing emission, which forms a mixed polarization
radiation with radial and axial polarized elements. Based on lasing radiation mechanism of evanescent-wave pumped WGM fibre
laser, the observed polarization properties are well explained.
Chinese Science Bulletin 04/2012; 55(7):567-572. · 1.32 Impact Factor