TY - JOUR
T1 - III-Nitride-based planar lightwave circuits for long wavelength optical communications
AU - Hui, Rongqing
AU - Wan, Yueting
AU - Li, Jing
AU - Jin, Sixuan
AU - Lin, Jingyu
AU - Jiang, Hongxing
N1 - Funding Information:
Manuscript received June 17, 2004; revised September 21, 2004. This work was supported in part by the National Science Foundation through “Ultra-High-Capacity Optical Communications and Networks” under Grants ECS-0 123 450, DMR-0203373, and ARO (DAAD19-03-1-0337).
PY - 2005/1
Y1 - 2005/1
N2 - Planar lightwave circuits based on III-nitride wide-bandgap semiconductors are proposed and the feasibility of developing III-nitride-based novel photonic integrated circuits for applications in fiber-optical communications is discussed. III-nitrides have low attenuation in the near-infrared wavelength region because of their wide bandgaps, while as semiconductors their refractive indexes can be modulated by carrier injection. III-nitrides are also well known for their ability to operate at high temperatures, high power levels and in harsh environments. These characteristics make III-nitrides ideal candidates for tunable optical phased-array (PHASAR) devices for optical communications. We have characterized the optical properties of Al x Ga1-x N epilayers in the 1550-nm wavelength region, including the refractive indexes and the impact of Al concentrations. Single-mode ridged optical waveguide devices using GaN-AlGaN heterostructures have been designed, fabricated and characterized for operation in the 1550-nm wave-length window. The birefringence of wurtzite GaN grown on sapphire substrate has been observed. Refractive indexes were found to be different for signal optical field perpendicular and parallel to the crystal c axis (n⊥ ≠ n//). More importantly, we found an approximately 10% change in the index difference Δn = n// - n⊥ with varying the waveguide orientation within the c plane, and a 60 ° periodicity was clearly observed. This is attributed to the hexagonal structure of the nitride materials. Various functional waveguide devices have been realized, including 2 × 2 directional couplers and eight-wavelength array-waveguide gratings. Theoretical predictions of temperature sensitivity and the efficiency of carrier-induced refractive change are provided.
AB - Planar lightwave circuits based on III-nitride wide-bandgap semiconductors are proposed and the feasibility of developing III-nitride-based novel photonic integrated circuits for applications in fiber-optical communications is discussed. III-nitrides have low attenuation in the near-infrared wavelength region because of their wide bandgaps, while as semiconductors their refractive indexes can be modulated by carrier injection. III-nitrides are also well known for their ability to operate at high temperatures, high power levels and in harsh environments. These characteristics make III-nitrides ideal candidates for tunable optical phased-array (PHASAR) devices for optical communications. We have characterized the optical properties of Al x Ga1-x N epilayers in the 1550-nm wavelength region, including the refractive indexes and the impact of Al concentrations. Single-mode ridged optical waveguide devices using GaN-AlGaN heterostructures have been designed, fabricated and characterized for operation in the 1550-nm wave-length window. The birefringence of wurtzite GaN grown on sapphire substrate has been observed. Refractive indexes were found to be different for signal optical field perpendicular and parallel to the crystal c axis (n⊥ ≠ n//). More importantly, we found an approximately 10% change in the index difference Δn = n// - n⊥ with varying the waveguide orientation within the c plane, and a 60 ° periodicity was clearly observed. This is attributed to the hexagonal structure of the nitride materials. Various functional waveguide devices have been realized, including 2 × 2 directional couplers and eight-wavelength array-waveguide gratings. Theoretical predictions of temperature sensitivity and the efficiency of carrier-induced refractive change are provided.
KW - Integrated optics
KW - Optical communication
KW - Planar waveguides
KW - Semiconductor devices
KW - Semiconductor materials
KW - Semiconductor waveguides
KW - Wavelength division multiplexing
UR - http://www.scopus.com/inward/record.url?scp=12844279962&partnerID=8YFLogxK
U2 - 10.1109/JQE.2004.838169
DO - 10.1109/JQE.2004.838169
M3 - Article
AN - SCOPUS:12844279962
SN - 0018-9197
VL - 41
SP - 100
EP - 110
JO - IEEE Journal of Quantum Electronics
JF - IEEE Journal of Quantum Electronics
IS - 1
ER -