研究目的
To demonstrate near-infrared lasing at 1 μm from dilute nitride-based multishell nanowires and evaluate their performance as coherent photon sources.
研究成果
The study successfully demonstrated NIR lasing at 1 μm from GaAs/GaNAs/GaAs nanowires with low nitrogen content, showing high threshold gain and spontaneous emission coupling factor. The lasing originated from the fundamental HE11a mode with good thermal stability. This work advances the use of dilute nitrides for efficient and tunable NIR nanowire lasers, with potential for room-temperature operation and applications in telecommunications and sensing.
研究不足
Lasing was constrained to temperatures up to 100 K due to the pump fluence limit of the laser excitation. The nanowires had imperfections such as tapering and nonperfect end facets, which could introduce additional losses. The study focused on optical pumping and did not explore electrical pumping or integration into practical devices.
1：Experimental Design and Method Selection:
The study involved growing GaAs/GaNAs/GaAs core/shell/cap nanowires using plasma-assisted Ga-catalyzed molecular beam epitaxy. Photoluminescence (PL) spectroscopy was used to characterize the lasing properties, including power-dependent and temperature-dependent measurements. Finite-difference-time-domain (FDTD) simulations were employed to analyze optical modes and threshold gain.
2：Sample Selection and Data Sources:
Single nanowires with specific lengths and structures (e.g., NW1, NW2, NW3) were selected for detailed analysis. Nanowires were transferred onto a gold substrate for better thermal conductivity during optical pumping.
3：List of Experimental Equipment and Materials:
Equipment included a Ti:sapphire laser for excitation, a He-flow cryostat for temperature control, a single grating monochromator, a charge-coupled-device camera for detection, and a linear-polarization analyzer. Materials included GaAs, GaNAs alloys, and gold substrates.
4：Experimental Procedures and Operational Workflow:
Nanowires were grown on Si substrates, transferred to gold, and subjected to μ-PL measurements in a backscattering geometry. Excitation was done with a continuous-wave or pulsed laser, and PL signals were analyzed for intensity, linewidth, and polarization.
5：Data Analysis Methods:
Rate equation analysis was used to derive threshold gain and spontaneous emission coupling factor. FDTD simulations calculated mode confinement and threshold gain. Statistical analysis of mode spacing and temperature dependence was performed.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
