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We study the effect of Coulomb correlation on the emission properties of the ground state exciton in zincblende CdSe/ZnS core-shell and in wurtzite ZnO quantum dots (QDs). We validate our theory model by comparing results of computed exciton energies of CdSe/ZnS QDs to photoluminescence and scanning near-field optical microscopy measurements. We use that to estimate the diameter of the QDs using a simple model based on infinitely deep quantum well and compare the results with the statistics of the atomic force microscopy scans of CdSe/ZnS dots, obtaining excellent agreement. Thereafter, we compute the energy fine structure of exciton, finding striking difference between properties of zincblende CdSe/ZnS and wurtzite ZnO dots. While in the former the fine structure is dominated by the dipole terms of the multipole expansion of the exchange interaction, in the latter system that is mostly influenced by Coulomb correlation. Furthermore, the correlation sizeably influences also the exciton binding energy and emission radiative rate in ZnO dots.

An inhomogeneous polymer-like thin film was deposited by the plasma enhanced chemical vapor deposition onto silicon single-crystal substrate whose surface was roughened by anodic oxidation. The inhomogeneous thin film with randomly rough boundaries was created as a result. This sample was studied using the variable-angle spectroscopic ellipsometry and spectroscopic reflectometry. The structural model including the inhomogeneous thin film, transition layer, and identically rough boundaries was used to process the experimental data. The scalar diffraction theory was used to describe the influence of roughness. The influence of the scattered light registered by the spectrophotometer due to its finite acceptance angle was also taken into account. The thicknesses and optical constants of the inhomogeneous thin film and the transition layer were determined in the optical characterization together with the roughness parameters. The determined rms value of the heights of roughness was found to be in good agreement with values obtained using AFM. The results of the optical characterization of the studied inhomogeneous thin film with rough boundaries were also verified by comparing them with the results of the optical characterization of the inhomogeneous thin film prepared using the same deposition conditions but onto the substrate with a smooth surface. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Synthetic data are of increasing importance in nanometrology. They can be used for development of data processing methods, analysis of uncertainties and estimation of various measurement artefacts. In this paper we review methods used for their generation and the applications of synthetic data in scanning probe microscopy, focusing on their principles, performance, and applicability. We illustrate the benefits of using synthetic data on different tasks related to development of better scanning approaches and related to estimation of reliability of data processing methods. We demonstrate how the synthetic data can be used to analyse systematic errors that are common to scanning probe microscopy methods, either related to the measurement principle or to the typical data processing paths.

Quantitative Data Processing in Scanning Probe Microscopy: SPM Applications for Nanometrology, Second Edition describes the recommended practices for measurements and data processing for various SPM techniques, also discussing associated numerical techniques and recommendations for further reading for particular physical quantities measurements. Each chapter has been revised and updated for this new edition to reflect the progress that has been made in SPM techniques in recent years. New features for this edition include more step-by-step examples, better sample data and more links to related documentation in open source software. Scanning Probe Microscopy (SPM) techniques have the potential to produce information on various local physical properties. Unfortunately, there is still a large gap between what is measured by commercial devices and what could be considered as a quantitative result. This book determines to educate and close that gap. Associated data sets can be downloaded from http://gwyddion.net/qspm/Features step-by-step guidance to aid readers in progressing from a general understanding of SPM principles to a greater mastery of complex data measurement techniques Includes a focus on metrology aspects of measurements, arming readers with a solid grasp of instrumentation and measuring methods accuracyWorked examples show quantitative data processing for different SPM analytical techniques