Near‐infrared intersubband emission from GaN/AlN quantum dots and quantum wells

We report on the observation of intersubband luminescence at room temperature from GaN/AlN quantum wells and quantum dots. The quantum wells are designed to exhibit three bound states in the conduction band. Optical pumping resonant with the e1-e3 transition (λ = 0.98 μm) is used to populate the e3 excited state. Emission corresponding to the e3-e2 transition is observed peaked at 2.13 (2.3) μm for heavily (lightly) doped quantum wells. We also report on the observation of room temperature emission at λ ≈ 1.5 μm from a stack of GaN/AlN QDs through resonantly-enhanced Raman scattering involving GaN LO-phonons. The quantum dot emission is ascribed to the pz-s intraband transition of the dots. We show that this process provides room for population inversion. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

[1]  Raffaele Colombelli,et al.  Room-temperature intersubband emission of GaN/AlN quantum wells at /spl lambda/=2.3 /spl mu/m , 2006 .

[2]  Joerg Heber,et al.  Comparative study of ultrafast intersubband electron scattering times at ̃1.55 μm wavelength in GaN/AlGaN heterostructures , 2002 .

[3]  Francois H. Julien,et al.  Electron confinement in strongly coupled GaN /AlN quantum wells , 2006 .

[4]  Claire F. Gmachl,et al.  Intersubband absorption at λ∼1.55 μm in well- and modulation-doped GaN/AlGaN multiple quantum wells with superlattice barriers , 2000 .

[5]  Maria Tchernycheva,et al.  Short wavelength (λ=2.13μm) intersubband luminescence from GaN∕AlN quantum wells at room temperature , 2007 .

[6]  Jin Wang,et al.  Optically pumped intersub-band emission in quantum wells , 1995 .

[7]  Paul Harrison,et al.  Simulation and design of GaN/AlGaN far-infrared (λ∼34 μm) quantum-cascade laser , 2004 .

[8]  Katsumi Kishino,et al.  Intersubband transition in (GaN)m/(AlN)n superlattices in the wavelength range from 1.08 to 1.61 μm , 2002 .

[9]  F. Julien,et al.  Systematic experimental and theoretical investigation of intersubband absorption in GaN/AlN quantum wells , 2006 .

[10]  Francois H. Julien,et al.  Si-doped GaN∕AlN quantum dot superlattices for optoelectronics at telecommunication wavelengths , 2006 .

[11]  Osamu Wada,et al.  Ultrafast intersubband relaxation (⩽150 fs) in AlGaN/GaN multiple quantum wells , 2000 .

[12]  Myriam Raybaut,et al.  Intersubband resonant enhancement of second-harmonic generation in GaN∕AlN quantum wells , 2006 .

[13]  Paul Harrison,et al.  Optically pumped terahertz laser based on intersubband transitions in a GaN∕AlGaN double quantum well , 2005 .