Growing fluorite single crystals by the method of inertial gradient solidification of the melt

   Aim. The purpose of this work is to obtain CaF₂ and CaF_2:Pb₂ + single crystals of by the method of inertial gradient solidification of the melt in a stationary crucible at an excess pressure of an inert gas, as well as to study the features of the impurity distribution in single crystals obtained by this method.
   Methodology. Fluorite single crystals 140 x 25 x 20 mm in size of good optical quality are obtained from a strongly overheated melt in a stationary crucible in a heat-saving graphite unit of the horizontal directional solidification (HDC) growth unit by inertial cooling of the furnace. The absorption spectra of CaF₂ and CaF₂:Pb₂+ crystals grown by the spontaneous crystallization method and the standard HSM method by drawing at a rate of 5 mm/h in an argon atmosphere are studied.
   Results. Single crystals of CaF₂ and CaF₂ :Pb²⁺ obtained by the method of inertial gradient inertial gradient solidification of the melt in a stationary crucible at an excess pressure of argon are synthesized and studied. The conditions for the process of this type of crystallization are established. The features of the impurity distribution for a single crystal obtained by this method are studied.
   Research implications. Growth studies of doped crystals show that, in comparison with the classical HDC method, in the case of inertial gradient solidification of the melt, there is a more uniform impurity distribution along the length of the crystals. A conclusion is made about the features of creating gaseous atmospheres for growing fluoride crystals using the HSM technology.

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