Mid-infrared tunable pulsed laser based on Cr2+-doped II–VI chalcogenide (Invited)

Abstract Cr2+-doped II–VI chalcogenides are attractive laser media for direct access to the mid-infrared (IR) region from 2 to 3 μ m. We have developed a mid-IR tunable laser using Cr:ZnSe and Cr:CdSe as laser media. We have used a Q-switched Tm:YAG laser as a pump source. For the Cr:ZnSe laser, the tuning range of 2.18–2.83 μ m and the maximum pulse energy of 4.98 mJ at 2.38 μ m were obtained with a pump energy of 22 mJ. For the Cr:CdSe laser, the tuning range of 2.22–3.04 μ m and the maximum pulse energy of 2.42 mJ at 2.54 μ m were achieved with a pump energy of 22 mJ. In addition, we have demonstrated a method of extending the mid-IR lasing region by a combined active medium technique with Cr:ZnSe and Cr:CdSe. We observed the broad tuning range from 2.15 to 3.04 μ m and the maximum pulse energy of 5.96 mJ at 2.44 μ m with a pump energy of 22 mJ.