Power stable 1.5–10.5 µm cascaded mid-infrared supercontinuum laser without thulium amplifier
Getinet Woyessa, Kyei Kwarkye, Manoj K. Dasa, Christian Petersen, Raghuraman Sidharthan, Shaoxiang Chen, Seongwoo Yoo, Ole Bang
Abstract
We demonstrate a simple and power stable 1.5–10.5 µm cascaded mid-infrared 3 MHz supercontinuum fiber laser. To increase simplicity and decrease cost, the design of the fiber cascade is optimized so that no thulium amplifier is needed. Despite the simple design with no thulium amplifier, we demonstrate a high average output power of 86.6 mW. Stability measurements for seven days with 8–9 h operation daily revealed fluctuations in the average power with a standard deviation of only 0.43% and a power spectral density stability of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>±</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>0.18</mml:mn> </mml:mrow> <mml:mspace width="thickmathspace"/> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi mathvariant="normal">B</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>/</mml:mo> </mml:mrow> <mml:mi mathvariant="normal">n</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> </mml:math> for wavelengths <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo><</mml:mo> </mml:mrow> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>10</mml:mn> </mml:mrow> <mml:mspace width="thickmathspace"/> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mtext>µ</mml:mtext> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> </mml:mrow> </mml:math> . The high-repetition-rate, robust, and cheap all-fiber design makes this source ideal for applications in spectroscopy and imaging.