β-Ga2O3 is an ultra-wide bandgap semiconductor with immense potential applications in high voltage, electronic devices, and deep-ultraviolet optoelectronic devices, etc. However, to date, the growth of bulk β-Ga2O3 crystals has predominantly utilized melt methods, which are heavily dependent on specific growth vessels. In this work, bulk crystal β-Ga2O3 with a size of 7 × 13 × 4 mm3 is grown using TeO2-Li2CO3 as flux by a top-seeded solution growth (TSSG) method for the first time. It is noteworthy that the saturation point of β-Ga2O3 in the flux has been reduced to 1023 K, significantly lower than its melting point of 2073 K. The resulting β-Ga2O3 crystal exhibits well-formed faces, predominantly the (010), (100), (01(-)1), and (11(-)1(-)) forms, which closely align with the ideal morphological predictions made by the Bravais-Friedel and Donnay-Harker methods.The full-width at half maximum (FWHM) of the rocking curves for the (010) oriented plane is determined to be 140.4″. This work provides a potential β-Ga2O3 crystal growth method with a little platinum loss at a low temperature.
Yi Yu,Chonghui Niu,Kai Shao,Mingjie Dan,Zhibin Wang,Yingying Wang,Jie Chen,Jiani Luo
A Ho 3+ :KBGM crystal with good quality and large size was successfully grown via TSSG method. The crystal’s structure, ambient-temperature polarized absorption and emission spectra and fluorescence lifetime were studied. The J-O theory was adopted to analyze the absorption spectra and results show that crystal exhibits relatively large intensity parameters Ω 2 and spectroscopic quality factor which is up to 3.12. At 453 nm, the absorption band is the strongest, and the corresponding cross-sections are 21.94 × 10 –20 cm 2 , 26.66 × 10 –20 cm 2 and 18.56 × 10 –20 cm 2 for the - X , - Y and - Z polarizations, respectively. The emission spectra also demonstrate the broad and strong emission band at 2030 nm. The FWHMs and cross-sections are 74 nm, 0.37 × 10 −20 cm 2 , 50 nm, 0.68 × 10 −20 cm 2 , and 49 nm 0.52 × 10 −20 cm 2 for the three polarizations, respectively. In addition, the crystal has a superior quantum efficiency which is as high as 97.1%. Taking all the analyses into account, it is reasonable to assert that the Ho 3+ :KBGM crystal an ideal candidate for ∼2 µm laser applications in many areas.