Air-core photonic-bandgap fiber-optic gyroscope

We report the demonstration of the first air-core photonic-bandgap fiber gyroscope. Because the optical mode in the sensing coil travels largely through air, which has much smaller Kerr, Faraday, and thermal constants than silica, far lower dependencies on power, magnetic field, and temperature fluctuations are predicted. With a 235-m fiber coil, we observe a minimum detectable rotation rate of /spl sim/2.7/spl deg//h and a long-term stability of /spl sim/2/spl deg//h, which are consistent with the Rayleigh backscattering coefficient of the fiber and comparable to that measured with a conventional fiber.