Effects of Gravity on ZBLAN Glass Crystallization

Abstract

The effects of gravity on the crystallization of ZrF(4)-BaF(2)-LaF(3)-AlF(3)-NaF glasses have been studied using the NASA KC-135 and a sounding rocket. Fibers and cylinders of ZBLAN glass were heated to the crystallization temperature in unit and reduced gravity. When processed in unit gravity the glass crystallized, but when processed in reduced gravity, crystallization was suppressed. A possible explanation involving shear thinning is presented to explain these results.

High-Power ZBLAN Glass Fiber Lasers: Review and Prospect

“…Technically, crystallization is an obstacle of fabricating high concentration ZBLAN fibers and 10 mol% is the maximum concentration of rare-earth ions in ZBLAN without inducing detrimental crystallization. Though zero-gravity environment has been proven to significantly reduce the crystallization during ZBLAN fabrication process [92], there is little feasibility of fabricating heavily Erdoped ZBLAN fibers (>10 mol%) for high efficiency lasers in the near further. Therefore, using large-mode-area core or multicore ZBLAN fibers will be the effective approach to obtain 100-watt-level output at 2.7 μm in the future.…”

Increasing the working temperature range of ZrF4-BaF2-LaF3-AlF3-NaF glass through microgravity processing

“…1 Since its discovery, there has been vast amounts of attention and research focused on the implementation and development for commercial applications. 3 The theoretical loss coefficient for ZBLAN is 0.01 dB∕km at 2.55-μm wavelength. These fibers also show promise in applications such as nuclear radiation-resistant links, highcapacity multiplexed fiber optics systems, and nonlinear optical applications.…”

“…ZBLAN glass fibers are excellent materials for the use in many applications such as fiber optics, fiber amplifiers, and lasers for cutting, drilling, and surgery. 3 Intrinsic and extrinsic processes hinder reaching the theoretical ultra-low loss coefficient. 2 The main advantage of ZBLAN glasses over other glasses, such as silica, is its superior infrared transmissibility.…”

“…These fibers also show promise in applications such as nuclear radiation-resistant links, highcapacity multiplexed fiber optics systems, and nonlinear optical applications. 3,5 The main obstacle with ZBLAN glass is the extrinsic process, which includes the problem of crystallization. The optical transmission spectrum for a ZBLAN fiber is from 0.3 μm in the ultraviolet to 7 μm in the infrared region.…”

“…1,3,[5][6][7] Therefore, microgravity processing shows promise in the work toward broadening the working temperature range of ZBLAN. 1,3,[5][6][7] Therefore, microgravity processing shows promise in the work toward broadening the working temperature range of ZBLAN.…”