Fiber-based portable optical frequency standard for telecommunication

Gas-filled hollow-core photonic crystal fibers are used to stabilize a fiber laser to the ¹³ C ₂ H2 P(16) (V ₁ + V ₃ ) transition at 1542 nm using saturated absorption. The fiber is encapsulated in glass cells for gas handling and compact free-space coupling, and packaged in a easy-to-use configuration. The system is showing a locking-point repeatability within 60 kHz with respect to a conventional acetylene vapor cell reference and an Allan deviation below 8 × 10 ^-11 (τ/s) ^-1/2 for 1 <; τ <; 1000 s.