T. A. Nguyen

Exciton spin relaxation time in quantum dots measured by continuous-wave photoluminescence spectroscopy

We demonstrate a method of measuring the exciton spin relaxation time in semiconductor nanostructures by continuous-wave photoluminescence. We find that for self-assembled CdTe quantum dots (QDs) the degree of circular polarization of emission is larger when exciting polarized excitons into the lower energy spin state (σ−-polarized) than in the case when the excitons are excited into the higher energy spin state (σ+-polarized). A simple rate equation model gives the exciton spin relaxation time in CdTe QDs equal to τS=4.8±0.3 ns, significantly longer than the QD exciton recombination time τR=300 ps.

Optically-induced magnetization of CdMnTe self-assembled quantum dots

We demonstrate that resonant excitation of CdMnTe self-assembled quantum dots creates an ensemble of spin-polarized magnetic polarons at B=0 T. The strong spatial confinement characteristic of quantum dots significantly increases the stability of magnetic polarons so that the optically-induced spin alignment is observed for temperatures >120 K.

Resonant spectroscopy of II-VI self-assembled quantum dots: Excited states and exciton-longitudinal optical phonon coupling

Using resonantly excited photoluminescence (PL) along with photoluminescence excitation (PLE) spectroscopies, we study the carrier excitation processes in

Exciton spin relaxation in quasiresonantly excited Cd Te ∕ Zn Te self-assembled quantum dots

\mathrm{CdTe}∕\mathrm{ZnTe}

Optical studies of spin relaxation in CdTe self-assembled quantum dots

and

Morphology Of CdTe/ZnTe Self‐Assembled Quantum Dots Studied By Excitation Spectroscopy

\mathrm{CdSe}∕\mathrm{ZnSe}

Resonant photoluminescence and excitation spectroscopy of CdSe/ZnSe and CdTe/ZnTe self-assembled quantum dots

self-assembled quantum dots (QDs). PLE spectra of single

Optical Properties of Semimagnetic Quantum Dots

\mathrm{CdTe}

Resonant photoluminescence imaging and the origin of excited states in self-assembled quantum dots

QDs reflect two major mechanisms for carrier excitation: The first, associated with the presence of sharp and intense lines in the spectrum, is a direct excited-state\char21{}ground-state transition. The second, associated with the appearance of up to four much broader excitation lines, is a longitudinal optical (LO) phonon-assisted absorption directly into the QD ground states. LO phonons with energies of both QDs and

Relaxation dynamics of bimodally distributed CdSe quantum dots

\mathrm{ZnTe}