# Is it possible to directly pump a laser using sunlight?

Typically in the old days one would use a flash tube to pump a ruby crystal. Is there any way, or any lasing material, that could use concentrated sunlight directly for either continuous or pulsed operation? I am familiar with some attempts but the materials available seem rather limited

• Sunlight has such a broad spectrum that I suspect many things could theoretically be pumped by it. The efficiency will be very low however. BTW, are you familiar with the Martian atmosphere CO$_2$ laser? – Chris Mueller Mar 30 '15 at 19:30
• It probably already exists – fffred Mar 30 '15 at 20:09
• It indeed exists, and is developed further. DOI: 10.1364/OE.21.025107 – Jarosław Komar Mar 31 '15 at 4:23