Continuous Wave Quantum Cascade Lasers With Reduced Number of Stages

Quantum cascade lasers: 25 years after the first demonstration

“…Experimentally we have verified the performance for a 20 gain stage QCL [8] as seen in Figure 5. Lyakh and his colleagues have explored this concept further by showing that use of smaller number of gain stages and a broader mesa for the QCL still results in a high beam quality output with higher power output [9].…”

“…Finally, AOM tuned QCL system permits simultaneous operation on two independently controlled wavelengths by an application of two different RF frequencies. Each wavelength can be tuned and switched independently by controlling the respective RF [8]. This capability makes it possible to carry out pump-probe studies of materials in the MWIR/LWIR region and also provides a tool for estimating intrinsic QCL lifetimes [13].…”

“…The increase in single emitter power output will require rethinking fundamental QCL structure design for higher wall plug efficiency, since thermal management is a very critical part of increasing single emitter power. One of the important steps that is being explored at present is the quantify the improvement that is possible if we use 10 to 30 gain stages in a QCL as opposed to the current 40-50 gain stages [8].…”

Генерация Квантово-Каскадного Лазера С Тонкой Верхней Обкладкой

“…Конструкция с двухфононным резонансным рассеянием носителей заряда использована при построении активной области [13,14]. Для исследования конструкции волновода с тонкой верхней обкладкой толщина слоя InP уменьшена до 750 nm (n = 1 • 10 17 cm −3 ) в сравнении с конструкциями волновода с толстой верхней обкладкой [15]. Толщина фосфида индия в 750 nm соответствует объему белого фосфора в крекере, предварительно перегнанного из красной фазы, что позволяет исключить шаг дополнительного преобразования во время эпитаксии и, как следствие, возможной корректировки потоков индия и галлия при последующем выращивании контактных слоев InGaAs.…”

Impact of Cascade Number on the Thermal Properties of Broad‐Area Quantum Cascade Lasers

“…One way to fabricate QCL devices with a high degree of heat extraction efficiency is using the buried heterostructure (BH) configuration, where the QCL active region is “buried” in a material with high thermal conductivity and high electrical resistance. Another appealing way to efficiently extract the heat is to fabricate QCL with a small number of cascades . This newer approach may allow higher cw power and brightness by using wider stripes with more total lasing volume than possible in BH designs .…”