Optical limiting, nonlinear refraction and nonlinear absorption of the associates of Cd₀₅Zn₀₅S quantum dots and dyes

Abstract

The optical limiting properties of alloyed CdZnS quantum dots associated with erythrosine dye are analyzed using 532 nm, 40 ps pulses. We show that joint influence of saturable absorption, reverse saturable absorption and two-photon absorption cause the optical limiting of 532 nm radiation at the pulse energies exceeding 1 mJ. The nonlinear refraction and nonlinear absorption of these quantum dots associated with different organic dyes were studied using 1064 nm and 532 nm radiation. The nonlinear refraction index and nonlinear absorption coefficient of CdZnS quantum dots were measured at λ = 1064 nm to be 2 × 10 cm W and 1.2 × 10 cm W, while the reverse saturable absorption of CdZnS quantum dots and erythrosine at λ = 532 nm was almost two orders larger. The potential applications of these quantum dots for high-order harmonic generation are discussed.

About Modern Research in the Field of Complex Sulfide Compounds (State and Trends)

“…A similar study of this complex sulfide is also reflected in the following works [11,32] and in earlier studies [38,23,29].…”

Photoluminescence Decay of Colloidal Quantum Dots: Reversible Trapping and the Nature of the Relevant Trap States

“…Since the first studies reporting the observation and interpretation of size-dependent absorption and emission in nanometer-sized colloidal semiconductor crystals (colloidal quantum dots, QDs), − these materials have been intensively investigated theoretical and experimentally due to fundamental scientific interest and bearing in mind their potential applications: imaging and sensing, − light harvesting and photovoltaics, − lasing, , photocatalysis, , optoelectronics, optical limiters, and infrared emitters and detectors. − Interfaces are crucial factors in the majority of these applications, since the chemical and physical properties of QDs (and assemblies of QDs), like those of any other colloidal particle, − are naturally conditioned by the nature of their surface (composition, geometry), surrounding environment, and the interactions between the two, in ways that are often not fully understood. For the most commonly studied type of QDs, that is, those consisting of the inorganic semiconductor nanocrystal proper covered by surfactant molecules (ligands), this means the interactions between (i) the surface of the inorganic core, − (ii) the ligands coating that surface, ,,,,− and (iii) the surrounding medium (solvent, polymer matrix, etc., including ions and other species, as well as the ligand molecules nonbonded to the surface of the inorganic core). ,− …”

Cell Imaging Using Two-Photon Excited CdS Fluorescent Quantum Dots Working within the Biological Window

“…Two-photon absorption, a molecular excitation process by the simultaneous absorption of two photons, has attracted growing interest in many areas for its broad application in photonics and biophotonics such as microscopy, data storage, optical limiting, microfabrication [1,2,3,4], etc. Two photon absorption technology has many advantages, especially for bioimaging, such as minimum photo-damage to living organisms, high spatial resolution and contrast, and high light-penetration depth in tissues [5,6].…”