Wavelength- and dispersion-tunable ultrafast holmium-doped fiber laser with dual-color operation
Maria Pawliszewska, Anna Dużyńska, Mariusz Zdrojek, Jarosław Sotor
Abstract
We present a versatile ultrafast holmium-doped fiber laser with an intracavity Martinez compressor. The compressor enables continuous dispersion control, spectral filtering, and dual-color operation of the laser. Mode locking is supported for net cavity dispersion values ranging from highly anomalous ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>−</mml:mo> <mml:mn>1.42</mml:mn> <mml:mspace width="thickmathspace"/> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="normal">p</mml:mi> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </mml:msup> </mml:mrow> </mml:math> ) to net normal ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mn>0.3</mml:mn> <mml:mspace width="thickmathspace"/> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="normal">p</mml:mi> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </mml:msup> </mml:mrow> </mml:math> ), and wavelength tuning of the optical solitons is obtained in a 2021–2096 nm span. Dual-color pulsed operation of the laser is reached by implementing a mechanical bandstop filter within the compressor. The repetition rate offset of the two emitted frequency combs can be tuned in a 3–8 kHz range by adjusting the net cavity dispersion, or by changing the beam block diameter. We show that a relatively simple fiber resonator integrated with a Martinez compressor can serve as a highly tunable laser source.