Recent progress in transition metal doped Ⅱ-Ⅵ mid-IR lasers

摘要

Recent progress in transition metal doped Ⅱ-Ⅵ semiconductor materials (mainly Cr~(2+):ZnSe) makes them the laser sources of choice when one needs a compact system with continuous tunability over 2-3.1 μm, output powers up to 2.7 W, and high (up to 70%) conversion efficiency. The unique combination of technological (low-cost ceramic material) and spectroscopic characteristics make these materials ideal candidates for "non-traditional" regimes of operation such as microchip and multi-line lasing. This article reviews these non-traditional Cr-doped mid-IR lasers as well as describes emerging Fe~(2+):ZnSe lasers having potential to operate at room temperature over the spectral range extended to 3.7-5.1 μm. In addition to effective RT mid-IR lasing transition metal doped Ⅱ-Ⅵ media, being wide band semiconductors, hold potential for direct electrical excitation. This work shows the initial steps towards achieving this goal by studying Cr~(2+), Co~(2+), and Fe~(2+) doped quantum dots. We have demonstrated a novel method of TM doped Ⅱ-Ⅵ quantum dots fabrication based on laser ablation in liquid environment. TM doped Ⅱ-Ⅵ quantum dots demonstrated strong mid-IR luminescence. It opens a new pathway for future optically and electrically pumped mid-IR lasers based on TM doped quantum confined structures.