Technological parameters of growing KY_1–xYb_x(WO₄)₂ single crystals by the modified Czochralski method

The results of growing KY_1–xYb_x(WO₄)₂ (KYW:Yb) crystals from a melt solution by the modified Czochralski method are presented. A thermal setup for semi-automatic growth has been developed and manufactured. The methodological features and temperature conditions for growing crystals on this setup have been worked out. The conditions for efficient heat and mass transfer for growing high-quality crystals have been studied. A method for fusing the charge for growing crystals with constant weight control has been determined. The temperature-concentration fields of crystallization were studied for the controlled growth of KYW:Yb crystals using the modified Czochralski method. It has been found that the axial temperature gradient above the melt solution surface should be 5–7 °C/cm. The results of the study can be used to develop a technology for growing KYW single crystals and to create, on their basis, an element base for laser systems emitting at a wavelength of about 1.0 µm.

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