Optical emission from rare-earth-doped fluoride fibers has thus far been limited to less than 4 μm. We extend emission beyond this limit by employing an indium fluoride (${\mathrm{InF}}_3$) glass fiber as the host, which exhibits an increased infrared transparency over commonly used zirconium fluoride (ZBLAN). Near-infrared pumping of a dysprosium-doped ${\mathrm{InF}}_3$ fiber results in broad emission centered around 4.3 μm, representing the longest emission yet achieved from a fluoride fiber. The first laser emission in an ${\mathrm{InF}}_3$ fiber is also demonstrated from the 3 μm dysprosium transition. Finally, a frequency domain excited state lifetime measurement comparison between fluoride hosts suggests that multiphonon effects are significantly reduced in indium fluoride fiber, paving the way to more efficient, longer wavelength lasers compared to ZBLAN fibers.

中文翻译：

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掺s氟化铟（InF ₃）光纤的发射超过4μm，并发出中红外激光

迄今为止，稀土掺杂的氟化物纤维的光发射被限制为小于4μm。我们通过使用氟化铟（${\mathrm{信息量}}_3$）玻璃纤维作为主体，与常用的氟化锆（ZBLAN）相比具有更高的红外透明度。掺s的近红外泵浦${\mathrm{信息量}}_3$纤维导致宽的发射集中在4.3μm左右，这是氟化物纤维迄今为止获得的最长的发射。第一个激光发射${\mathrm{信息量}}_3$还从3μmtransition过渡中证实了这种纤维。最后，氟化物主体之间的频域激发态寿命测量比较表明，氟化铟光纤中的多声子效应显着降低，与ZBLAN光纤相比，它为更高效，更长波长的激光器铺平了道路。