abstract

• Circularly polarized photoluminescence (PL) spectroscopy measured at 19 K on GaAs/AlGaAs symmetric and asymmetric double quantum wells (DQW) is reported. The PL is obtained by exciting the sample with a circularly polarized (left or right) laser in order to create an initial unbalanced distribution of electron spins in the conduction band and, in this way, obtain the electron spin lifetime (Formula presented.). The effects of the excitation laser wavelength are estimated by exciting with laser wavelengths of 701.0, 787.0, 801.5, and 806.5 nm. The increase of (Formula presented.) with the excitation wavelength is attributed to the lower initial quasimomentum k of the excited carriers, which also reduces spin–orbit relaxation processes. (Formula presented.) is found to be higher in asymmetric DQWs: this is attributed to the wider QWs in these samples, which reduces spin relaxation due to the Dresselhaus mechanism. In addition, a smaller contribution from the Rashba mechanism is also detected by comparing samples with built-in electric fields of different orientations defined by doped barrier layers. © 2022 Wiley-VCH GmbH.

authors

• Biermann K.
• Flores-Rangel G.
• Lastras Martínez Luis Felipe
• Rodríguez-Tapia L.E.
• Ruiz-Cigarrillo O.
• Santos P.V.

publication date

• 2022-01-01

funding provided via

• FC 2016‐02‐2093  Grant

published in

• Physica Status Solidi (B) Basic Research  Journal

keywords

• photoluminescence; quantum wells; spin dynamics Circular polarization; Electric fields; Electrospinning; Gallium arsenide; III-V semiconductors; Laser excitation; Photoluminescence; Photoluminescence spectroscopy; Quantum well lasers; Spin dynamics; Asymmetric double quantum wells; Circularly-polarized; Double quantum-well; Excitation lasers; GaAs/AlGaAs; Laser wavelength; Laser-wavelength effects; Polarized photoluminescence; Quantum-wells; Symmetrics; Semiconductor quantum wells

Digital Object Identifier (DOI)

• 10.1002/pssb.202100612

PubMed ID

start page

end page

volume

• 259

issue

• 4