Mid-infrared intersubband electroluminescence from a single-period GaAs/AlGaAs triple barrier structure

Abstract

This letter reports the observation of intersubband electroluminescence from a single-period resonant tunneling structure. Intersubband emission (λ≈8.4 μm), with a full width at half maximum of 7 meV, was observed from a GaAs/AlGaAs triple barrier structure with quantum well widths of 66 and 33 Å. The emission was coupled out of the sample by a metallic grating with a period of 5 μm deposited on the surface. The intensity of emission follows the resonance behavior in the I–V characteristics. As the temperature increases from 10 to 200 K, the emission intensity decreases monotonically by a factor of ∼2 and the emission energy shifts down slightly (ΔE≈2.7 meV). The temperature dependence of the emission energy is explained by a combination of thermal broadening of the electron distribution and the nonparabolicity of the conduction bands.

Ultrafast Phenomena in Semiconductors

“…Currently, many activities focus on realizing a quantum cascade laser in the GaAs/AIGaAs material system [288]. Strong mid-infrared electroluminescence has been found in a number of structures [289][290][291][292][293][294][295]. Recently, the first oparation of a GaAsl AIGaAs quantum cascade laser was reported [296].…”

Electric-field-dependent subband population in undoped GaAs/(Al,Ga)As quantum-cascade structures

“…For the investigation of the subband population in unipolar devices, photoluminescence (PL) spectroscopy has been used in cases in which only one hole subband is involved in the interband transitions [7][8][9][10]. In general, the hole dynamics has to be known, since the population of both electrons in the conduction subbands and holes in the valence subbands determine the PL intensity.…”

Photonic crystals in the optical regime — past, present and future

“…transitions between di!erent states in the same or neighbouring quantum wells and typically a multitude of these transitions is cascaded in order to provide su$cient gain. In most cases, InGaAs/InAlAs multilayers are used, but there has also been rapid progress in the GaAs/AlGaAs system [144,145]. The wavelength range demonstrated so far is between 3 m and 17 m.…”