Quantum cascade lasers(QCLs)are unipolar quantum devices based on inter-sub-band transitions.They break the electron-hole recombination mechanism in traditional semiconductor lasers,overcome the long-lasting bottlenec...Quantum cascade lasers(QCLs)are unipolar quantum devices based on inter-sub-band transitions.They break the electron-hole recombination mechanism in traditional semiconductor lasers,overcome the long-lasting bottleneck which is that the emission wavelength of semiconductor laser is completely dependent on the bandgap of semiconductor materials.Therefore,their emission wavelength is able to cover the mid-infrared(mid-IR)range and the"Terahertz gap"that is previously inaccessible by any other semiconductor lasers.After thirty years development,QCLs have become the most promising light source in the mid-IR and THz regime.In this paper,we are going to present the strategies and methodologies to achieve high-power,high-wall-plug-efficiency(WPE)QCLs with high-brightness in room temperature continuous-wave(cw)operation at 3-300μm.We will also review the recent breakthroughs in QCL community,especially the high-power,high WPE intersubband lasers in room temperature cw operation.展开更多
基金support of the Walter P.Murphy Chair Professorship at the McCormick School of Engineering,Northwestern UniversityCo-author Professor Feihu Wang formerly a Research Assistant Professor at CQD/Northwestern University and currently based in China gratefully acknowledges the support of Guangdong Basic and Applied Basic Research Foundation(2023A1515012793,2024B1515020117)。
文摘Quantum cascade lasers(QCLs)are unipolar quantum devices based on inter-sub-band transitions.They break the electron-hole recombination mechanism in traditional semiconductor lasers,overcome the long-lasting bottleneck which is that the emission wavelength of semiconductor laser is completely dependent on the bandgap of semiconductor materials.Therefore,their emission wavelength is able to cover the mid-infrared(mid-IR)range and the"Terahertz gap"that is previously inaccessible by any other semiconductor lasers.After thirty years development,QCLs have become the most promising light source in the mid-IR and THz regime.In this paper,we are going to present the strategies and methodologies to achieve high-power,high-wall-plug-efficiency(WPE)QCLs with high-brightness in room temperature continuous-wave(cw)operation at 3-300μm.We will also review the recent breakthroughs in QCL community,especially the high-power,high WPE intersubband lasers in room temperature cw operation.
