Photonic-crystal fibers with a photonic band gap tunable within the range of 930–1030 nm

Abstract
The physical principles of photonic-crystal fibers with a photonic band gap tunable in the visible and near-IR spectral ranges are demonstrated. Direct numerical integration of the Maxwell equations with the use of the finite-difference time-domain technique reveals the possibility of creating holey fibers with a photonic-crystal cladding whose photonic band gap lies within the frequency range characteristic of widespread solid-state femtosecond lasers. The fabrication of holey fibers with a pitch of the two-dimensional periodic structure of the cladding less than 500 nm allowed us to experimentally observe a photonic band gap in transmission spectra of holey fibers tunable within the range of 930–1030 nm. This photonic band gap is satisfactorily described within the framework of the proposed numerical approach based on the finite-difference time-domain method.