Probing the longitudinal electric field of Bessel beams using second-harmonic generation from nano-objects

Research output: Contribution to journalArticleScientificpeer-review


Research units

  • Tampere University of Technology


Non-diffractive Bessel beams are receiving significant interest in optical microscopy due to their remarkably large depth of field. For example, studies have shown the superiority of Bessel beams over Gaussian beams for volumetric imaging of three-dimensionally thick or extended samples. However, the vectorial aspects of the focal fields of Bessel beams are generally obscured when traditional methods are used to characterize their three-dimensional point-spread function in space, which contains contributions from all optical field components. Here, we show experimentally the three-dimensional spatial distribution and enhanced depth of field of the longitudinal electric field components of a focused linearly-polarized Bessel beam. This is done through second-harmonic generation from well-defined vertically-aligned gallium-arsenide nanowires, whose second-order response is primarily driven by the longitudinal fields at the beam focus.


Original languageEnglish
Article number084011
Pages (from-to)1-6
JournalJournal of Optics
Issue number8
Publication statusPublished - 1 Aug 2017
MoE publication typeA1 Journal article-refereed

    Research areas

  • Bessel beams, longitudinal electric field, nonlinear microscopy, second-harmonic generation, semiconductor nanowires

ID: 14580281