Špokas Aivaras, Zelioli Andrea, Bičiūnas Andrius, Čechavičius Bronislovas, Glemža Justinas, Pralgauskaitė Sandra, Kamarauskas Mindaugas, Bukauskas Virginijus, Spigulis Janis, Chiu Yi-Jen, Matukas Jonas, Butkutė Renata
Center for Physical Sciences and Technology, 10257 Vilnius, Lithuania.
Institute of Photonics and Nanotechnology, Faculty of Physics, Vilnius University, 10257 Vilnius, Lithuania.
Micromachines (Basel). 2025 Apr 26;16(5):506. doi: 10.3390/mi16050506.
We explore quantum well laser diodes for applications in pulse oximetry based on two material systems, namely, classical AlGaAs and a rather exotic GaAsBi, with lasing at around 800 nm and 1100 nm, respectively. These spectral regions and material families were selected due to their closely matched effective penetration depths into soft tissue. An improved design of the band structure of device active areas was tested on both material systems, yielding enhancement of the two main parameters, namely, output power and threshold current. A maximum emission power of the AlGaAs laser diode was registered at 4.9 mW (I = 60 mA, λ = 801 nm). For the GaAsBi-based devices, the target emission of 1106 nm was measured in pulsed mode with a peak output power of 9.4 mW (I = 3 A). The most optimized structure was based on three GaAsBi quantum wells surrounded by parabolically graded AlGaAs barriers. This structure was capable of 130 mW peak power (I = 2 A, λ = 1025 nm) along with a more than tenfold decrease in threshold current to 250 mA compared to a classical rectangular quantum well active region.
我们基于两种材料体系（即传统的AlGaAs和相当奇特的GaAsBi）探索用于脉搏血氧测定的量子阱激光二极管，其激光发射波长分别约为800nm和1100nm。选择这些光谱区域和材料族是因为它们对软组织的有效穿透深度密切匹配。在这两种材料体系上都测试了器件有源区能带结构的改进设计，提高了两个主要参数，即输出功率和阈值电流。AlGaAs激光二极管的最大发射功率记录为4.9mW（I = 60mA，λ = 801nm）。对于基于GaAsBi的器件，在脉冲模式下测得目标发射波长为1106nm，峰值输出功率为9.4mW（I = 3A）。最优化的结构基于三个被抛物渐变AlGaAs势垒包围的GaAsBi量子阱。与传统的矩形量子阱有源区相比，这种结构能够实现130mW的峰值功率（I = 2A，λ = 1025nm），同时阈值电流降低到250mA，降幅超过十倍。
