High peak power λ∼3.3 and 3.5 μm InGaAs/AlAs(Sb) quantum cascade lasers operating up to 400 K

Abstract

We demonstrate λ∼3.5 μm and λ∼3.3 μm strain compensated In0.7Ga0.3As/AlAs(Sb)/InP quantum cascade lasers operating in pulse regime at temperatures up to at least 400 K. Peak optical power exceeding 3.5 W at 300 K has been achieved at both wavelengths for 10 μm wide 4 mm long lasers with high reflectivity coated back facets. Threshold current densities of 2.5 kA/cm2 and 3.5 kA/cm2 have been observed at 300 K for the devices emitting at λ∼3.5 μm and λ∼3.3 μm, respectively.

Quantum Cascade Laser With Unilateral Grating

“…[8]. In 0.53 Ga 0.47 As spacer layers of 200 nm were grown around the ∼ 1.32 μm thick laser core by molecular beam epitaxy on a low doped (3 −5 × 10 17 cm −3 ) n-type InP substrate.…”

Investigations of carrier scattering into L‐valley in λ = 3.5 µm InGaAs/AlAs(Sb) quantum cascade lasers using high hydrostatic pressure

“…However, due to the relatively close proximity of the L-and X-minima, which are close to the top G-laser levels in InGaAs quantum wells, potential carrier scattering from the G-laser levels into these indirect valleys is of potential concern. For example, the lowest L-valley in these devices is located only $38 meV [6] above the G-laser level and the X-valleys are at least 81 meV above the L-valleys. In this work, InGaAs/AlAs(Sb) QCLs on InP substrates emitting at l ¼ 3.5 mm at room temperature are investigated by using cryogenic and hydrostatic pressure techniques to identify importance of inter-valley scattering whereby the carrier scattering into the indirect valleys can be studied in detail.…”

“…The structure of these devices is (in nanometers): 2. [6]. The devices have cavity lengths of 1.5 and 3 mm with a 10 mm ridge width.…”

“…Further details of the growth and device fabrication can be found elsewhere [6]. The structure of these devices is (in nanometers): 2.…”

Long-infrared InAs-based quantum cascade lasers operating at 291 K (λ=19 μm) with metal-metal resonators

“…The quantum cascade (QC) laser concept is in principle material independent, since its operating principle relies on intersubband unipolar transitions in multiple quantum well (QW) systems: 1 the width of the QW-and not the semiconductor material-sets the emission wavelength. To date, QC lasers (QCLs) have been demonstrated in three major material families: InGaAs/AlInAs on InP substrates; GaAs/AlGaAs on GaAs substrates; and antimonides materials, such as InAs/AlSb on InAs substrates, 5 InGaAs/AlAsSb on InP substrates, 22 or-recently-InGaAs/GaAsSb on InP. 23 As a matter of fact, each of these materials best suits a specific wavelength range, due to differences in electronic effective mass, conduction band offset, and index of refraction.…”