Survey for rare earth doped chalcogenide glasses with high intensity of luminescence.

硫系玻璃具有声子能量低、折射率高、红外透过率高等特点。掺Er(Er^&lt；3+&gt；)硫系玻璃是1550 nm附近有源光波导应用的重要候选材料。我们研究了掺Er^&lt；3+&gt；的硫系玻璃。以Ge(5N)、Se(5N)、Ga(5N)和Er_2S_3(3N)为原料，采用熔体淬火技术，从1000℃到水中淬火制备了块体样品。根据Er~(2+)在1450 nm处的透过率和对Er~(2+)和Gt~(3+)的吸收效率来评价Er的溶解度。除了低(&lt；3at.%)Ga浓度外，玻璃允许在所有玻璃形成区溶解1at.%的Er。在GeSe_2和Ga_2Se_3的化学计量关系线上，当Er的含量为4at.%左右时，Er的溶解度最佳。光致发光是由波长为980 nm的激光激发的。当Ga含量为10-14at.%时，在联络线上观察到最大的光致发光强度。我们发现，当Er~(2+)浓度达到2at.%时，发光强度随Er~(2+)浓度的增加而成比例增加，超过这个浓度后，发光强度不变或减小。因此，在这些玻璃基质中，Er^&lt；3+&gt；离子似乎很好地分散和光学活性，直到Er浓度约为2at.%。掺Er~(2+)、In~(3+)、Gt~(3+)的玻璃在Ga含量超过18.at%时，玻璃基质变得不均匀。由于这种行为只在掺Er玻璃中观察到，Er^&lt；3+&gt；离子的存在似乎有助于玻璃基质的失稳(相分离或结晶)。观察了热处理和Se对Te的替代作用。在不改变荧光光谱的情况下，发光强度增加到50%-100%。Er^&lt；3+&gt；离子将保持在-Se^&lt；-δ&gt；-Ga^&lt；+δ&gt；-的共价键附近，因为这两个原子的电负性差异导致了Se和Ga之间的离子键。然后，Er^&lt；3+&gt；离子被一定数量的Se原子吸引。

Chalcogenide glasses have useful properties such as low phonon energies, high refractive index, and high transmittance in the infrared. Erbium (Er^<3+>) doped chalcogenide glasses are important candidates for active optical wave guide applications at around 1550nm. We investigated Er^<3+> doped chalcogenide glasses. Bulk samples were prepared using Ge (5N), Se (5N), Ga (5N), and Er_2S_3 (3N) by melt quenching technique by quenching from 1000 ℃ to water. We evaluated the solubility of Er according to optical transmission at 1450nm and efficiency of absorption for Er^<3+>. The glasses allowed to solute 1at.% of Er over the all glass forming region except for low (<3at.%) Ga concentration. On the tie-line of stoichiometry between GeSe_2 and Ga_2Se_3 the solubility of Er is best as about 4 at.% of Er. The photoluminescence (PL) was excited from a laser operating at a wavelength of 980 nm. The maximum intensity of PL was observed on the tie-line at 10-14at.% of Ga. We found that PL intensity increased proportionally with Er^<3+> concentration up to 2 at.% and than it is constant or decreases above this concentration. Consequently Er^<3+> ions seem to be well dispersed and optically active up to Er concentration of about 2 at.% in these glass matrices. The glass matrix of Er^<3+> doped glasses becomes inhomogeneous above 18.at.% of Ga content. As this behaviour was observed only for Er-doped glasses, the presence of Er^<3+> ions seem to aid glass matrix destabilization (phase separation, or crystallization). The effect of thermal annealing and substitution of Se to Te were observed. The PL intensity increased to 50%-100% without the change of PL spectra. Er^<3+> ions would stay near the covalent bond of -Se^<-δ>-Ga^<+δ>- because the difference in the electronegativity of both atoms caused the ionic bonding between Se and Ga. Then Er^<3+> ion attracted to some number of Se atoms.