Single-frequency microchip Nd lasers

TLDR

Optically pumped, single‑frequency Nd‑doped solid‑state lasers have been fabricated in flat‑flat microchip cavities diced from large dielectrically coated wafers of various crystals. A Nd:YAG microchip laser with a 730‑µm cavity achieved single‑mode operation from below 1 mW to over 40× threshold, with >30 % slope efficiency, a 5 kHz instrument‑limited linewidth, and demonstrates substantial cost and complexity reductions for small lasers and electro‑optic devices.

Abstract

Optically pumped, single-frequency, Nd-doped, solid-state lasers have been constructed using flat-flat cavities, which were diced from large dielectrically coated wafers of various crystals. For example, a Nd:YAG laser with a cavity length of 730 microm has operated at room temperature in a single longitudinal mode from a threshold of less than 1 mW to greater than 40 times the threshold. Theslope efficiency was greater than 30%. Heterodyne measurements showed an instrument-limited linewidth of 5 kHz. The microchip lasers demonstrate ways to reduce greatly the cost and complexity offabricating small lasers and electro-optic devices.