Related Experiment Video
Updated: Jan 29, 2026
Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
Low-Threshold InP Nanowire Hetero-Photonic Crystal Surface-Emitting Lasers
Navoda Jayawardana1, Matthew T Larson1, Chia-Wei Tu1
1Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States.
Abstract:
Nanowire photonic crystal surface-emitting lasers (PCSELs) hold considerable promise as on-chip coherent light sources for photonic integrated circuits. However, they face stringent demands regarding laser performance and compactness of the active region. To address these challenges, we designed and evaluated the lasing characteristics of InP nanowire hetero-PCSELs. These PCSELs feature a tightly compact, hexagonally shaped inner lasing region with side lengths ranging from 1.5 to 15 μm, surrounded by a larger, off-resonant outer photonic crystal designed to lower the lasing threshold. Inner PCSELs with an area smaller than the focus of the pump light but with side length exceeding 3 μm showed markedly reduced threshold power and threshold gain compared to large area PCSELs. The threshold reductions are attributed to back reflection enhancement at the heterolattice interface as the laser energy lies in the forbidden photonic gap of the outer photonic crystal array. This study paves the path toward ultracompact, low-threshold electrically pumped nanowire PCSELs for integration into photonic circuits.
Related Concept Videos
02:42Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
01:25Crystal Growth: Principles of Crystallization
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
01:16Surface Tension and Surface Energy
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
01:14Wood Surfacing
The equipment used in the surfacing process is a plane equipped with rotating blades. This tool efficiently smoothens the wood surface and can...