High quality Er,Yb:CaGdAlO₄ (Er,Yb:CALGO) single crystals with a diameter around 1 mm were successfully grown and investigated for the first time by the laser heated pedestal growth (LHPG) method. The cracking mechanism of (001) planes was studied via density functional theory (DFT). The doping concentration of Er³⁺ and Yb³⁺ was calculated by X-ray fluorescence analysis (XRF). The XRD pattern confirms that the phase of Er,Yb:CALGO is consistent with pure CALGO and the crystal quality was measured through Laue back-reflection measurements. The optical properties including absorption spectra, mid-infrared fluorescence spectra and fluorescence lifetime of the Er³⁺, Yb³⁺ co-doped CALGO crystal were measured at room temperature to assess its potential for improving absorption efficiency. Further research found that the disordered structure of the CALGO crystal could achieve wider absorption and emission bands accompanied with efficient energy transfer from the excited Yb³⁺ to Er³⁺. Our results indicated that the Er,Yb:CALGO crystal is a promising material for achieving tunable mid-infrared lasers.

中文翻译：

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LHPG法生长的Er，Yb：CaGdAlO4晶体的开裂机理和光谱性质

成功地生长了直径约1 mm的高质量Er，Yb：CaGdAlO ₄（Er，Yb：CALGO）单晶，并首次通过激光加热基座生长（LHPG）方法进行了研究。通过密度泛函理论（DFT）研究了（001）面的开裂机理。通过X射线荧光分析（XRF）计算Er ³⁺和Yb ³⁺的掺杂浓度。X射线衍射图谱证实Er，Yb：CALGO的相位与纯CALGO一致，并且通过劳厄背反射测量法测量了晶体质量。光学性质包括Er ³⁺，Yb ^3+的吸收光谱，中红外荧光光谱和荧光寿命在室温下测量共掺杂的CALGO晶体，以评估其改善吸收效率的潜力。进一步的研究发现，CALGO晶体的无序结构可以实现更宽的吸收和发射带，并具有从激发的Yb ³⁺到Er ^3+的有效能量转移。我们的结果表明，Er，Yb：CALGO晶体是实现可调谐中红外激光的有前途的材料。