Contents lists available at ScienceDirect Journal of Non-Crystalline Solids journal homepage: www.elsevier.com/locate/jnoncrysol One-step micro-modification of optical properties in silver-doped zinc phosphate glasses by femtosecond direct laser writing G.Yu. Shakhgildyan a, ⁎ , A.S. Lipatiev a , M.P. Vetchinnikov a , V.V. Popova a , S.V. Lotarev a , N.V. Golubev a , E.S. Ignat'eva a , M.M. Presniakov b , V.N. Sigaev a a D. Mendeleev University of Chemical Technology of Russia, Moscow 125373, Russia b National Research Centre “Kurchatov Institute”, Moscow 123182, Russia ARTICLE INFO Keywords: Direct laser writing Femtosecond laser Silver nanoparticles Silver nanoclusters Form birefringence Phosphate glass ABSTRACT We demonstrate the possibility of joint formation of fluorescent silver clusters and plasmonic silver nanoparticles spatially confined in micron-sized domains by the one-step femtosecond direct laser writing (DLW) without subsequent heat treatment in zinc phosphate glasses with different concentration of silver. We show that DLW in glass induces local micro-modification of optical properties resulted in the appearance of luminescence, ab- sorption and form birefringence in domains. Variation of laser pulse energy allows controlling the micro- modification process and tuning of optical properties. We propose a possible mechanism for observed phe- nomena that includes local chemical redistribution of glass network modifiers during DLW process. We believe that ability to form complex 3D shapes of luminescent, plasmonic and birefringent structures embedded in dielectric transparent glass materials opens new routes for the design of nanophotonic devices and multi- dimensional optical memory. 1. Introduction Nowadays nanotechnology represents many ways for processing and tailoring of materials structure at the nanoscale to initiate unique optical properties. One of the significant directions for nanotechnology is development and control of complex metallic nanostructures that can support surface plasmon resonance (SPR) or exhibit fluorescence in particular over large three-dimensionally (3D) areas with high flex- ibility and speed [1,2]. These nanostructures are of great interest for future applications in nonlinear optics, plasmonic sensing, bioimaging, color displaying and so forth [3]. Despite the advantages of numerous nanolithographic techniques, the 3D manufacturing process is still limited by slow processing speed, complexity in implementation and high production cost. On the contrary, femtosecond (fs) direct laser writing (DLW) has become a powerful tool for the fast 3D modification of optical materials due to multiphoton absorption of ultrashort pulses [4]. DLW paves the way for the development of composite materials with advanced optical properties and fabrication of functional photonic devices such as in- tegrated waveguides, optical switches, phase plates, 3D optical memory, etc. [5]. Among other materials (polymers, crystals, glass- ceramics) oxide glasses are of particular interest as an object for DLW due to their general availability, low cost, thermal, and chemical stability and excellent optical properties in visible and near-infrared (NIR) ranges that is necessary for the most plasmonic and photonic applications. Along with the properties of glass, parameters of a laser beam applied DLW such as pulse duration, energy and repetition rate play crucial role in the induced material modifications that can give rise to various phenomena such as refractive index change, modification of chemical composition, phase transitions, formation of bubbles or bi- refringent nanogratings spatially confined in the vicinity of the beam waist [4,5]. Silver and gold nanostructures are among the most promising can- didates for future applications in sensing, plasmonics and future op- toelectronic integration due to their unique and tunable optical prop- erties: depending on their size they can exhibit intensive fluorescence as nanoclusters (less 1–2 nm in size) or possess well-detectable SPR as nanoparticles (> 3–4 nm in size). Both properties are highly sensitive to size and shape of nanostructures [3,6] and can be tuned in a wide spectral range. However, there are no ways for the further development of complex integrated devices without proper stabilization in dielectric matrix and possibility for precise manipulation of such nanostructures. Thus fs DLW in glasses doped with the noble metal ions offers an op- portunity for space-selective generation and stabilization of metal na- nostructures in hard dielectric matrix due to series of thermal and chemical processes that take place during DLW [7]. https://doi.org/10.1016/j.jnoncrysol.2017.12.011 Received 21 August 2017; Received in revised form 29 November 2017; Accepted 4 December 2017 ⁎ Corresponding author. E-mail address: gshah@muctr.ru (G.Y. Shakhgildyan). Journal of Non-Crystalline Solids xxx (xxxx) xxx–xxx 0022-3093/ © 2017 Elsevier B.V. All rights reserved. Please cite this article as: Shakhgildyan, G.Y., Journal of Non-Crystalline Solids (2017), https://doi.org/10.1016/j.jnoncrysol.2017.12.011