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Self-aligned non-dispersive external cavity tunable laser.

We are reporting on a novel self-aligned non-dispersive external cavity laser (ECL) based on thick volume holographic gratings (VHG). The ECL is tunable and operates with single mode and broad area multimode laser diodes. We experimentally demonstrate tunable single frequency operation at 405 nm and 785 nm. The tunable ECL concept is also experimentally tested with high power broad area laser diodes near 780 nm. The passive alignment feature of the cavity is expected to reduce the assembly cost of tunable ECLs.