Surface Plasmonic Lasing in Micro-Nanostructures of Silicon Excited by using Pulsed Infrared Lasers

Surface plasmon is a possible candidate to break the diffraction limit and open the door for developing nanolasers on silicon chips. A new step in this development involves the choice of the structures and compositions for better surface plasmonic emission. The micro-nanostructures were fabricated by using a nanosecond pulsed laser on silicon surface, in which the surface plasmonic emission is stronger. The group of emission peaks with multiple-longitudinal-mode occurs in the optical gain curve. Interestingly, the quantum energy of surface plasmon with 140[Formula: see text]meV has been measured at first, which is related to the peak interval (about 62[Formula: see text]nm) of longitudinal modes in the surface plasmonic lasing spectra. The surface plasmonic lasing near 865[Formula: see text]nm was observed in the Purcell cavity with Si–Cr–Si layers excited by using pulsed lasers at 1064[Formula: see text]nm. Surface plasmonic structure induced with photons was observed by using the reflection Talbot effect image, in which the mechanism of the surface plasmonic lasing can be explored. The physical model of the surface plasmonic laser has been built on the energy levels of the micro-nanostructures of Si.

Polarization Angle Dependence of Optical Gain in a Hybrid Structure of Alexa-Flour 488/M13 Bacteriophage

We measured optical modal gain of a dye–virus hybrid structure using a variable stripe length method, where Alexa-fluor-488 dye was coated on a virus assembly of M13 bacteriophage. Inspired by the structural periodicity of the wrinkle-like virus assembly, the edge emission of amplified spontaneous emission was measured for increasing excited optical stripe length, which was aligned to be either parallel or perpendicular to the wrinkle alignment. We found that the edge emission showed a strong optical anisotropy, and a spectral etalon also appeared in the gain spectrum. These results can be attributed to the corrugated structure, which causes a similar effect to a DFB laser, and we also estimated effective cavity lengths.

GaN-Based Bipolar Cascade Lasers with 25nm Wide Quantum Wells

Utilizing self-consistent numerical simulation in good agreement with measurements, we analyze internal device physics, performance limitations, and optimization options for a unique laser design with multiple active regions separated by tunnel junctions, featuring surprisingly wide InGaN quantum wells. Contrary to common assumptions, these quantum wells are revealed to allow for perfect screening of the strong built-in polarization field, while optical gain is provided by higher quantum levels. However, internal absorption, low p-cladding conductivity, and self-heating are shown to strongly limit the laser performance.