Demonstration of a 34 nm monolithic continuously tunable VCSEL at 1.55 µm combined with liquid crystal

A 1.55 μm emitting tunable vertical cavity surface emitting laser (VCSEL) is fabricated, using an intracavity nematic liquid crystal layer. Half cavity VCSEL are realized on InP(001), based on quantum wells associated with broadband dielectric mirror, following by the insertion of a 3 μm thick liquid crystal layer in the cavity. Room temperature laser emission is obtained in the 1.5 μm wavelength range. Single mode emission with a continuously tuning range of 34 nm is demonstrated by applying a voltage on the liquid crystal layer as low as 2.4 V. Output tunable VCSEL peak emission is polarized along the liquid crystal extraordinary axis. Considering that the full liquid crystal index variation for voltage close to 10 V results in a wavelength tuning as high as 100 nm, these preliminary results demonstrate the interest of nematic liquid crystal in achieving polarization stabilized widely tunable and monolithic VCSELs.