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Photostable second-harmonic generation from a single KTiOPO4 nanocrystal for nonlinear microscopy

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Pages (from-to)1332-1336
Number of pages5
Issue number9
Publication statusPublished - Sep 2008
Externally publishedYes
Publication typeA1 Journal article-refereed


A study was conducted to report the observation and the characterization of nanometric-sized crystals extracted by centrifugation from KTP (potassium titanyl phosphate) powder. In situ atomic force microscopy (AFM) analysis of its size and analysis of its second-harmonic emission properties were performed for a well-isolated single nanocrystal. The highly efficient nonlinear response leads to the emission of several SHG photons and in a photostable and blinking-free manner due to non-resonant coherent interaction. The study retrieved the in situ three-dimensional crystal orientation by recovering the radiation pattern from the recorded defocused images. Solution-based chemical synthesis of KTP nanocrystals with a monodisperse size controlled by capping agents should lead to optimized KTP nanocrystallites and to a more accurate estimate of the size-detection threshold. Fully characterized nano-KTPs are also attractive for the development of novel schemes of nonlinear microscopy.


  • Nanocrystals, Nanoparticles, Nonlinear microscopy, Second-harmonic generation