Mid-infrared emissions from Ho3+ in Ga2S3-GeS2-Sb2S3 glass

作者：Ichikawa Manabu; Ishikawa Yo ichi; Wakasugi Takashi; Kadono Kohei^*

来源：Journal of Luminescence, 2012, 132(3): 784-788.

DOI：10.1016/j.jlumin.2011.11.007

• Sulfide Glass
• Ho3+
• Mid-infrared Emission
• Population Analysis
• Low-Phonon Energy
• Rare-Earth

Emission properties were investigated in the infrared region for Ga2S3-GeS2-Sb2S3 glasses doped with Ho3+. We performed Judd-Ofelt analysis and lifetime measurements of the I-5(4), I-5(5), and I-5(6) levels, which are the initial levels of the mid-infrared emissions between 3 to 5 mu m of Ho3+. The quantum efficiencies reached approximately 18%, 64%, and similar to 100% for the I-5(4), I-5(5), and I-5(6), respectively. Population analyses were carried out from the relative intensities of the emissions in the near-infrared region. We investigated the dependences on the Ho3+ ion concentration of the population ratio of the initial levels to the final levels, [initial]/[final], of the mid-infrared emissions. The population ratio of [I-5(5)]/[I-5(6)] decreased with increase of the Ho3+ concentration while those of [I-5(4)]/[I-5(5)] and [I-5(6)]/[I-5(7)] increased. Particularly, the former, [I-5(4)]/[I-5(5)], rapidly increased because of the strong concentration quenching of the I-5(5) level through cross relaxation. It was found that the population inversion for the 4.8 mu m emission due to the transition, I-5(4) -%26gt; I-5(5), was achieved at high Ho3+ concentration in the present experiments.

• 出版日期2012-3