In a laser (12, 18) with a laser resonator (13), the laser resonator (13) has a non-linear optical loop mirror (1, 1′), NOLM, which is adapted to guide counter-propagating portions of laser pulses, and to bring the counter-propagating portions of laser pulses into interference with each other at an exit point (4) of the NOLM (1, 1′). The non-linear optical loop mirror (1, 1′) contains a non-reciprocal optical element (7, 7′) on a linear section of the NOLM. In addition to the NOLM, the laser resonator (13) has a linear cavity section. The linear section of the NOLM and the linear cavity section (19) are reassembled on a microoptical bench (112) or within a cylindrical carrier (112).