Publication:
Absolute two-photon absorption cross-sections of single-exciton states in semiconductor nanocrystals

Дата
2020
Journal Title
Journal ISSN
Volume Title
Издатель
Научные группы
Организационные подразделения
Организационная единица
Инженерно-физический институт биомедицины
Цель ИФИБ и стратегия развития – это подготовка высококвалифицированных кадров на базе передовых исследований и разработок новых перспективных методов и материалов в области инженерно-физической биомедицины. Занятие лидерских позиций в биомедицинских технологиях XXI века и внедрение их в образовательный процесс, что отвечает решению практикоориентированной задачи мирового уровня – диагностике и терапии на клеточном уровне социально-значимых заболеваний человека.
Выпуск журнала
Аннотация
© 2020 SPIE.Semiconductor nanocrystals (SNCs), in particular, quantum dots (QDs) and nanoplatelets (NPLs), have orders of magnitude higher two-photon absorption cross-sections (TPACS) than organic dyes, what paves the way to their advanced applications in bioimaging, sensing, and optoelectronics. Traditionally, z-scan and two-photon photoluminescence (PL) excitation spectroscopy are used to determine the TPACS values. The main disadvantage of both methods is the necessity to know the exact sample concentration. In this study, we describe an approach to the TPACS determination from the analysis of two-photon-excited (TPE) PL saturation in CdSe(core)/ZnS/CdS/ZnS(multishell) QDs and CdSe NPLs. The results obtained for NPLs using developed approach are significantly smaller than those obtained by the z-scan method and are close to the values obtained for QDs. We assume that this discrepancy occurs due to the fact, that unlike the z-scan technique, the TPE PL saturation method measures the TPACS only for single-exciton states because of the low PL quantum yields of multiexciton states. Therefore, there is no need to know the concentration, which eliminates the corresponding estimation error. Thus, the measurement of TPE PL saturation in SNCs makes it possible to determine the absolute values of the TPACS of single-exciton states, which are more informative for applications of TPE PL than the TPACS of mixed multiexciton states.
Описание
Ключевые слова
Цитирование
Absolute two-photon absorption cross-sections of single-exciton states in semiconductor nanocrystals / Krivenkov, V. [et al.] // Proceedings of SPIE - The International Society for Optical Engineering. - 2020. - 11345. - 10.1117/12.2556259
Коллекции