Emission at 1.6 μm from InAs Quantum Dots in Metamorphic InGaAs Matrix

Abstract

Growth of InAs quantum dots (QDs) in metamorphic InGaAs matrix for long‐wavelength laser applications on GaAs substrates by molecular beam epitaxy (MBE) is demonstrated. Metamorphic InGaAs matrix is based on a five‐step graded InGaAs metamorphic buffer layer (MBL) with a final indium composition of about 40%. Reciprocal space mapping for the asymmetrical (−2 2 4) and (2 2 4) reflections along the [−1 1 0] and [1 1 0] directions shows anisotropic relaxation along these two directions. The metamorphic InGaAs matrix is more relaxed along [−1 1 0] direction but nearly fully strained along [1 1 0] direction. InAs QDs are embedded in two InGaAs confining layers with the same indium composition. Emission at 1.6 μm from metamorphic InAs QDs and 1.42 μm emission from metamorphic InGaAs matrix at room temperature (RT) are observed, respectively. The activation energy of ≈94.6 meV is obtained.

Flat metamorphic InAlAs buffer layer on GaAs(111)A misoriented substrates by growth kinetics control

“…Recently, a key device emerged for quantum in-5 formation technologies: quantum dot (QD) based single and entangled photon emitters operating at the telecom-wavelength band for the quantum key distribution over long distances [5,6]. This is usually based on InAs QDs on GaAs and InP substrates and requires the use of an InGa(Al)As MMBL to obtain a long wavelength emission [7,8,9,10], since the typical InAs/GaAs QD emission is around 1 µm [11,12].…”

Impact of Built‐In Electric Field on the Emission Characteristics of InAs/GaAs Quantum Dot Laser Structure

“…[ 3 ] InAs/GaAs QD lasers are a stirring source for telecommunication applications [ 4 ] and long‐wavelength emission. [ 5,6 ] A careful investigation of the QD laser structure is crucial for revealing the characteristic device parameters, a different mode of operation, [ 7,8 ] and time‐ and temperature‐resolved optical performance. [ 9,10 ] An understanding of the thermally enhanced occupational probability of quantized energy states [ 11 ] is of primary importance for the analysis and operation of advanced QD lasers.…”

E‐Band InAs/GaAs Trilayer Quantum Dot Lasers

“…As one candidate approach, the introduction of an InGaAs metamorphic buffer layer on the GaAs substrate was utilized to modify the crystal lattice constant toward that of InAs bulk to reduce the strain inside InAs QDs. [ 15–17 ] Another approach is introducing a new structure including two closely stacked QD layers called bilayer QDs where the first layer is grown as a template to offer a strain field for the second layer. [ 12,18–21 ] These two layers are called the seed QD layer and active QD layer, respectively.…”