Transverse mode formation in microlasers by combined gain- andindex-guiding

摘要

The formation of transverse modes in end-pumped microlasers withncombined index- and gain-guiding is investigated theoretically, We studynthe case of a planoconcave cavity pumped by means of a Gaussian opticalnfield in the frame of the effective index method and the mean-fieldnlimit. We find crossings of the modal gains as the cavity losses arenvaried. Ring patterns are observed in both the near- and far-fieldnprofiles in qualitative agreement with the experiments. We study thenbad-cavity region and observe one compact trapped gain-guided mode withnlarge modal gain, and many other deformed index-guided modes with muchnless gain