Pulling Doped-YAG Single-crystal Fibers

Pulling bulk crystal into fiber is suitable for
dvice applications in optical communications because
of its structural similarity to silica fiber. Among
fiber growth techniques, the laser-heated pedestal
growth method (LHPG) was adopted. It is crucible
free and can therefore produce high-quality single
crystals. However, interface loss of the fiber is
one of the main causes of optical loss. In order to
reduce the loss, a proper method to clad the fiber
is important for high performance device. For laser
application, high-efficient Nd:YAG lasers were
demonstrated using gradient-index crystal fibers.
For ASE and optical amplifier applications, Cr4+:YAG
crystal fiber was studied due to its fluorescence
just covering the low loss window of optical fiber.
To reduce the fiber diameter and propagation loss, a
novel cladding technique, codrawing LHPG, was
developed. A double-clad fiber was successfully
grown by the technique. As much as 2.36 mW of ASE
with a bandwidth of 265 nm was demonstrated. Up to
16-dB of gross gain at 1470 nm was also achieved. It
is the first transition metal-doped fiber amplifier
in the optical communication band.

Autorentext
Chia-Yao Lo received his Ph.D. in electro-optical engineering
from National Sun Yat-sen University. He is currently an
assistant professor in the Institute of Optoelectronic Sciences
at National Taiwan Ocean University.

Klappentext
Pulling bulk crystal into fiber is suitable for dvice applications in optical communications because of its structural similarity to silica fiber. Among fiber growth techniques, the laser-heated pedestal growth method (LHPG) was adopted. It is crucible free and can therefore produce high-quality single crystals. However, interface loss of the fiber is one of the main causes of optical loss. In order to reduce the loss, a proper method to clad the fiber is important for high performance device. For laser application, high-efficient Nd:YAG lasers were demonstrated using gradient-index crystal fibers. For ASE and optical amplifier applications, Cr4+:YAG crystal fiber was studied due to its fluorescence just covering the low loss window of optical fiber. To reduce the fiber diameter and propagation loss, a novel cladding technique, codrawing LHPG, was developed. A double-clad fiber was successfully grown by the technique. As much as 2.36 mW of ASE with a bandwidth of 265 nm was demonstrated. Up to 16-dB of gross gain at 1470 nm was also achieved. It is the first transition metal-doped fiber amplifier in the optical communication band.