Short wavelength operation of a 10 m perimeter ring laser gyroscope

We report on the operation of a 10 m perimeter, helium–neon based ring laser gyroscope on the 3s₂ → 2 p6 (611.8 nm) and 3s₂ → 2 p₁₀ (543.4 nm) transitions of neon. Cavity Q factors of 1.5 × 10¹² and 3.8 × 10¹¹ are obtained for 611.8 and 543.4 nm operation, inferred from measured ring-down times of 485 and 110 µs, respectively. For Sagnac frequencies, due to Earth rotation, of 205.14 and 230.96 Hz, minimum resolvable rotation rates of 80 and 226 prad/s are achieved for integration times of around 100 s. While environment limited performance is achieved for operation at 611.8 nm, it is found that a restrictive gas pressure regime must be utilized for the 543.4 nm lasing wavelength. As a consequence, the output photon count is low, which limits its intrinsic sensitivity for rotation rate measurements.