Low Loss GaN at 1550 nm

We report absorption loss coefficients at 1550 nm of free-standing GaN grown by hydride vapor phase epitaxy. We measured propagation loss values at numerous locations of the facets and observed an average of 2.41 dB/cm and 1.85 dB/cm for TE and TM polarizations, respectively, in the low loss region of the sample. The minimum loss values in the sample were found to be 0.82 dB/cm (TE) and 0.61 dB/cm (TM). The ability to achieve such low propagation loss coefficients in GaN opens up the possibility of using this material in a variety of integrated optics and nonlinear optics applications.