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Appl. Phys. A 80, 1647–1652 (2005)

Applied Physics A

DOI: 10.1007/s00339-004-3090-3

Materials Science & Processing

a. podlipensky
a. abdolvand
g. seifertu
h. graener

Femtosecond laser assisted production
of dichroitic 3D structures in composite
glass containing Ag nanoparticles
Fachbereich Physik, Martin-Luther-Universität Halle-Wittenberg, 06099 Halle, Germany

Received:17 May 2004/Accepted: 10 October 2004
Published online: 25 November 2004 • © Springer-Verlag 2004
ABSTRACT Three-dimensional, permanent anisotropic modifications in glass containing spherical Ag nanoparticles are
demonstrated using multicolor fs laser irradiation. The method
can produce dichroism by deformation of nanoparticles to oblong shapes oriented parallel to the laser polarization. Usingsamples with a vertical gradient of the fill factor of Ag nanoparticles in the glass substrate and an accordingly inhomogeneous
broadening of the surface plasmon band, modifications in various depths can be made using different excitation wavelengths.
The induced modifications are reversible: heating to ≈ 600 ◦ C
restores the spherical shape of Ag nanoparticles. This technique
could be used inmanufacturing of different, 3D, polarization
and wavelength selective micro-devices such as polarizers, filters, gratings, display and rewriting optical 3D data storage
devices.
PACS 78.55.Hx;

1

78.67.Bf; 78.40.Ha

Introduction

In the last two decades, composite materials containing metal nanoparticles found various applications in different fields of science and technology [1–3].Linear and
nonlinear optical properties of such materials are determined
by surface plasma oscillations of the metal clusters. These
surface plasmon (SP) resonances depend strongly on shape,
distribution and concentration of the nanoparticles as well as
on the surrounding dielectric matrix. This offers the opportunity to manufacture very promising new nonlinear materials, nanodevices and opticalelements by manipulation of the
nanostructural properties of the metal particles. Laser-based
techniques to modify shape and arrangement of the metal
clusters [4–10] are of great interest since they provide a very
powerful and flexible tool to control and optimize the linear
and nonlinear optical properties of these materials. Recently,
it was discovered that a permanent transformation ofinitially
spherical metal nanoparticles embedded in soda-lime glass
into ellipsoidal (or more general, non-spherical) shapes can be
made by irradiation with intense fs laser pulses [11–15]. This
effect, the physics of which has been studied extensively in the
past few years [11–15], allows for the production of colored
and dichroitic patterns in the glass, which were demonstrated
so far onlyfor two-dimensional (2D) geometries.
u Fax: +49-345-5527221, E-mail: g.seifert@physik.uni-halle.de

In this paper, it is shown that also three-dimensional (3D)
anisotropic modifications of the optical properties are possible in glass samples where the volume fill factor of initially
spherical Ag nanoparticles shows a significant gradient along
a direction normal to the glass surface (e.g., asshown here, decreases from the surface into the depth of the glass). The idea
for this technique is based on the fact that Ag nanoparticles
with different fill factor exhibit different spectral width and
position of their SP band, and can thus selectively be excited
by different laser wavelengths.
2

Spectral properties of composite glass
with high fraction of Ag nanoparticles

Theabsorption spectrum of a single metal particle
is characterized by the well-known Mie resonance [1, 16, 17]
occurring at the SP frequency ωsp under the following condition:
Re εi (ωsp ) = −2εh .

(1)

Here εi (ω) and εh are the complex dielectric constant of metal
and surrounding matrix, respectively. This results in resonant
enhancement of the dipole moment of the metal inclusion in
a...