Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses
Quasi-periodic microstructures containing dislocations are formed on the surfaces of metals and semiconductors under irradiation with high-power femtosecond laser pulses. Interpretation of microstructures as a result of interference of the incident plane wave and surface waves leads to the logica...
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
2014
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| Цитувати: | Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses / N.G. Zubrilin, I.M. Dmitruk // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2014. — Т. 17, № 2. — С. 165-167. — Бібліогр.: 10 назв. — англ. |
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irk-123456789-1183662017-05-31T03:06:07Z Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses Zubrilin, N.G. Dmitruk, I.M. Quasi-periodic microstructures containing dislocations are formed on the surfaces of metals and semiconductors under irradiation with high-power femtosecond laser pulses. Interpretation of microstructures as a result of interference of the incident plane wave and surface waves leads to the logical conclusion about the relationship of dislocations in the interference fringes with optical vortices in surface wave. 2014 Article Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses / N.G. Zubrilin, I.M. Dmitruk // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2014. — Т. 17, № 2. — С. 165-167. — Бібліогр.: 10 назв. — англ. 1560-8034 PACS 42.50.Tx, 78.68.+m, 79.20.Eb, 81.05.Bx http://dspace.nbuv.gov.ua/handle/123456789/118366 en Semiconductor Physics Quantum Electronics & Optoelectronics Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
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Quasi-periodic microstructures containing dislocations are formed on the
surfaces of metals and semiconductors under irradiation with high-power femtosecond
laser pulses. Interpretation of microstructures as a result of interference of the incident
plane wave and surface waves leads to the logical conclusion about the relationship of
dislocations in the interference fringes with optical vortices in surface wave. |
| format |
Article |
| author |
Zubrilin, N.G. Dmitruk, I.M. |
| spellingShingle |
Zubrilin, N.G. Dmitruk, I.M. Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses Semiconductor Physics Quantum Electronics & Optoelectronics |
| author_facet |
Zubrilin, N.G. Dmitruk, I.M. |
| author_sort |
Zubrilin, N.G. |
| title |
Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
| title_short |
Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
| title_full |
Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
| title_fullStr |
Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
| title_full_unstemmed |
Manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
| title_sort |
manifestation of optical vortices on the surface of solids under irradiation with femtosecond laser pulses |
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| publishDate |
2014 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/118366 |
| citation_txt |
Manifestation of optical vortices on the surface of solids
under irradiation with femtosecond laser pulses / N.G. Zubrilin, I.M. Dmitruk // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2014. — Т. 17, № 2. — С. 165-167. — Бібліогр.: 10 назв. — англ. |
| series |
Semiconductor Physics Quantum Electronics & Optoelectronics |
| work_keys_str_mv |
AT zubrilinng manifestationofopticalvorticesonthesurfaceofsolidsunderirradiationwithfemtosecondlaserpulses AT dmitrukim manifestationofopticalvorticesonthesurfaceofsolidsunderirradiationwithfemtosecondlaserpulses |
| first_indexed |
2025-07-08T13:51:03Z |
| last_indexed |
2025-07-08T13:51:03Z |
| _version_ |
1837086973699817472 |
| fulltext |
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 2. P. 165-167.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
165
PACS 42.50.Tx, 78.68.+m, 79.20.Eb, 81.05.Bx
Manifestation of optical vortices on the surface of solids
under irradiation with femtosecond laser pulses
N.G. Zubrilin, I.M. Dmitruk
Institute of Physics, NAS of Ukraine
46, prospect Nauky, 03680 Kyiv, Ukraine,
Phone: 38 (044)525-16-70, e-mail: zubrilin@iop.kiev.ua
Abstract. Quasi-periodic microstructures containing dislocations are formed on the
surfaces of metals and semiconductors under irradiation with high-power femtosecond
laser pulses. Interpretation of microstructures as a result of interference of the incident
plane wave and surface waves leads to the logical conclusion about the relationship of
dislocations in the interference fringes with optical vortices in surface wave.
Keywords: laser processing, surface wave, optical vortex.
Manuscript received 21.01.14; revised version received 23.04.14; accepted for
publication 12.06.14; published online 30.06.14.
1. Introduction
It is known [1-5] that under the action of plane-polarized
laser pulses with a wavelength λ on the surface of metals
and some semiconductors, structures in the form of
parallel strips with a period , somewhat smaller than
the wavelength λ, oriented perpendicular to the plane of
the electric vector of light, are observed.
There are several possible mechanisms of formation
of these structures. Proposed in [1] is an explanation of
the effect based on the concept of interference of the
incident and scattered along the surface electromagnetic
waves. There is also a hypothesis about the nature of these
structures as frozen capillary waves on the surface of the
molten by laser layer [6]. However, the most probable
mechanism of formation of these structures is associated
with interference of the incident and surface
electromagnetic waves excited by the incident wave on
the surface of metal at their scattering by roughness of the
metal surface [7].
In this paper, we report on the important feature of
laser-induced structures on the surface of metal, which,
as far as we know, hasn’t been still given proper
attention.
2. Experimental methods
The experiment was carried out at Femtosecond Laser
Center for collective use at the Institute of Physics, NAS
of Ukraine, by irradiating the metal surface with the Ti-
sapphire femtosecond laser system consisting of a
master oscillator Mira-900F and a regenerative amplifier
Legend HE. The laser pulse with the wavelength of
820 nm, duration of 140 fs, and energy of about 0.8 to
1 mJ was focused on the surface with a long focal length
lens. The spot size on the surface was 0.8…1 mm, which
corresponds to the power density of the order of 1012 up
to 1013 W/cm2, the time of irradiation was 0.4…2 s. If
desired, a larger surface area was treated, while the
sample was moved during irradiation at a constant
velocity of several millimeters per second. Thus, every
part of the surface was treated with hundreds to
thousands of laser pulses. Formation of quasi-periodic
structures on the surface was monitored visually by
appearance of bright light diffraction on the treated
areas.
The detailed study of morphology inherent to the
treated surface was performed with a scanning electron
microscope JEOL JXA-8200. The typical image of the
irradiated surface of tungsten is shown in Fig. 1. There is
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 2. P. 165-167.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
166
a quasi-periodic system of bands with the period ~0.5 μm,
which remains constant throughout the treated area.
However, you may notice that sometimes the band
breaks (indicated by arrows in Fig. 1) with the
corresponding deformation of the bands around, while the
distance between the bands remains unchanged. Thus,
dislocations occur in the system of bands. As noted above,
the obtained system of bands on the surface is most
logically explained as the result of interference of the
incident and surface waves (surface plasmon polariton in
the case of metals). In this case, disappearance of the
interference fringe indicates the change of the phase
difference of the interfering waves by 2π when going
around this point, i.e. the presence of the screw dislocation
of the wavefront of one of the waves – the optical vortex.
These dislocations in the interference pattern with vortex
beams are well known [8].
Similar structures were obtained on metals (W, Mo,
Ta, Ni, Ag, Pt). Preliminary experiments showed that
these structures are observed also on the surface of
semiconductors (Si for example).
Noteworthy is that in the stripes and between them
spherical shape nanostructures with the size
~30…100 nm are present (Fig. 2).
Fig. 1. Characteristic “forks” associated with the presence of
“optical vortices” in electromagnetic fields taking part in
formation of structures on the surface of tungsten.
Fig. 2. Image of treated tungsten surface with larger
magnification reveals nanostructures in the stripes and between
them.
3. Results and discussion
The beams with helical wavefront perturbations
(singular beams) occupy a special place among the wave
beams with a variable structure of the amplitude-phase
profile. This kind of disturbance causes the vortex nature
of the propagating light energy, which suggests the
existence of peculiar optical vortices [9].
To generate singular optical beams, most widely
used are the methods for direct conversion of the
spatially inhomogeneous phase of the light wave and
holographic interferometry methods of converting light
beams. In the first case, spiral phase plates or liquid
crystal spatial modulators are used. Another method to
generate singular beams is diffraction of the initial
Gaussian beam on special optical transparencies based
on computer-generated holograms [9].
Finally, we discuss briefly a possible mechanism of
formation of optical vortices when the metal surface is
irradiated by power femtosecond pulses.
Under “natural conditions”, most of the wavefront
dislocations of laser beams that cause the vortex
structure of the light field are observed in the scattering
of light by random media on the propagation path (for
example, when passing sufficiently large tract in the
atmosphere or scattering on very rough surfaces).
It is known that during irradiation of rough surfaces
with laser, speckles appear. In [10], it is pointed out for
the first time that the wavefront dislocations are inherent
to optical fields that have a speckle structure. For
monochromatic polarized beam with sufficiently
developed inhomogeneities of complex amplitude,
appearance of wavefront dislocations is inevitable [10].
When discussing the possible mechanism of
formation of optical vortices as a result of power laser
pulse interaction with the metal surface, note the
similarity of the resulting fringe pattern on the metal
surface with the transparencies used to produce beams
with vortices. Besides, as formation of the structures on
the surface occurs gradually, there takes place an
accumulation effect of sequential exposure from
hundreds or thousands of pulses. The surface of metal
may be not only a recording medium, but it can also
participate in formation of spatial distribution of the
amplitude and phase of the wavefront, i.e. operate as a
space-phase modulator. We can assume that initially
small surface roughnesses are minor points forming
wavefront dislocations, which then as a result of
interference with the incident plane wave form a quasi-
periodic structure with dislocation that in turn acts as a
phase modulator and so on. Thus, a positive feedback in
the system is realized as a result of formation of a
distinct stable self-consistent structure under the action
of laser pulses.
4. Conclusion
The study of periodic structures formed on the surface of
metals and semiconductors under irradiation with
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 2. P. 165-167.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
167
femtosecond laser pulses showed characteristic quasi-
periodic patterns with dislocations (broken stripes). The
offered interpretation associates these dislocations in
interference pattern with the presence of wavefront
dislocations – optical vortices on the surface or scattered
waves. Most distinct structures were observed on the
surface of tungsten, which is probably due to its high
melting point.
Acknowledgements
The authors thank V.B. Sobolev (Technical Center NAS
of Ukraine) for carrying out electron microscopy of the
samples. Partial financial support came from Ukrainian
State target scientific and technical program
Nanotechnologies and Nanomaterials for 2010-2014
project No. 1.1.3.11, 3.5.5.23.
References
1. D.C. Emmony, R.P. Howson, and L.J. Willis, Laser
mirror damage in germanium at 10.6 m // Appl.
Phys. Lett. 23, p. 598-600 (1973).
2. Zhou Guosheng, P.M. Fauchet, and A.E. Siegman,
Growth of spontaneous periodic surface structures
on solids during laser illumination // Phys. Rev. B,
26(10), p. 5366-5381 (1982).
3. J.F. Young, J.S. Preston, H.M. van Driel, and
J.E. Sipe, Laser-induced periodic surface structure.
II. Experiments on Ge, Si, Al, and brass // Phys.
Rev. B, 27(2), p. 1155-1172 (1983).
4. Kiminori Okamuro, Masaki Hashida, Yasuhiro
Miyasaka, Yoshinobu Ikuta, Shigeki Tokita, and
Shuji Sakabe, Laser fluence dependence of periodic
grating structures formed on metal surfaces under
femtosecond laser pulse irradiation // Phys. Rev. B,
82, p. 165417-5 (2010).
5. Litao Qi, Kazuhiro Nishii, and Yoshiharu Namba,
Regular subwavelength surface structures induced
by femtosecond laser pulses on stainless steel //
Opt. Lett. 34(12), p. 1846-1848 (2009).
6. T. Sano, M. Yanai, E. Ohmura, Y. Nomura,
I. Miyamoto, A. Hirose, K. Kobayashi, Femtosecond
laser fabrication of microspike-arrays on tungsten
surface // Appl. Surf. Sci. 247, p. 340-346 (2005).
7. S.R.J. Brueck and D.J. Ehrlich, Stimulated surface-
plasma-wave scattering and growth of a periodic
structure in laser-photodeposited metal films //
Phys. Rev. Lett. 48(24), p. 1678-1681 (1982).
8. L.A. Kazak, A.L. Tolstik, Formation of
superposition and stability of vortex optical beams
of different orders // Vestnik Belorusskogo
Gosudarstv. Universiteta, Ser. 1, №2, p. 3-7
(2010), in Russian.
9. M. Padgett, J. Courtial, L. Allen, Light’s orbital
angular momentum // Physics Today, 57(5), p. 35-
40 (2004).
10. N.B. Baranova, B.J. Zeldovich, A.B. Mamaev,
N.F. Pilipetskii, V.V. Shkunov, Wavefront
dislocations of speckle-inhomogeneous field
(theory and experiment) // JETP Lett. 33(4), p. 206-
210 (1981), in Russian.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2014. V. 17, N 2. P. 165-167.
PACS 42.50.Tx, 78.68.+m, 79.20.Eb, 81.05.Bx
Manifestation of optical vortices on the surface of solids
under irradiation with femtosecond laser pulses
N.G. Zubrilin, I.M. Dmitruk
Institute of Physics, NAS of Ukraine
46, prospect Nauky, 03680 Kyiv, Ukraine,
Phone: 38 (044)525-16-70, e-mail: zubrilin@iop.kiev.ua
Abstract. Quasi-periodic microstructures containing dislocations are formed on the surfaces of metals and semiconductors under irradiation with high-power femtosecond laser pulses. Interpretation of microstructures as a result of interference of the incident plane wave and surface waves leads to the logical conclusion about the relationship of dislocations in the interference fringes with optical vortices in surface wave.
Keywords: laser processing, surface wave, optical vortex.
Manuscript received 21.01.14; revised version received 23.04.14; accepted for publication 12.06.14; published online 30.06.14.
1. Introduction
It is known [1-5] that under the action of plane-polarized laser pulses with a wavelength λ on the surface of metals and some semiconductors, structures in the form of parallel strips with a period (, somewhat smaller than the wavelength λ, oriented perpendicular to the plane of the electric vector of light, are observed.
There are several possible mechanisms of formation of these structures. Proposed in [1] is an explanation of the effect based on the concept of interference of the incident and scattered along the surface electromagnetic waves. There is also a hypothesis about the nature of these structures as frozen capillary waves on the surface of the molten by laser layer [6]. However, the most probable mechanism of formation of these structures is associated with interference of the incident and surface electromagnetic waves excited by the incident wave on the surface of metal at their scattering by roughness of the metal surface [7].
In this paper, we report on the important feature of laser-induced structures on the surface of metal, which, as far as we know, hasn’t been still given proper attention.
2. Experimental methods
The experiment was carried out at Femtosecond Laser Center for collective use at the Institute of Physics, NAS of Ukraine, by irradiating the metal surface with the Ti-sapphire femtosecond laser system consisting of a master oscillator Mira-900F and a regenerative amplifier Legend HE. The laser pulse with the wavelength of 820 nm, duration of 140 fs, and energy of about 0.8 to 1 mJ was focused on the surface with a long focal length lens. The spot size on the surface was 0.8…1 mm, which corresponds to the power density of the order of 1012 up to 1013 W/cm2, the time of irradiation was 0.4…2 s. If desired, a larger surface area was treated, while the sample was moved during irradiation at a constant velocity of several millimeters per second. Thus, every part of the surface was treated with hundreds to thousands of laser pulses. Formation of quasi-periodic structures on the surface was monitored visually by appearance of bright light diffraction on the treated areas.
The detailed study of morphology inherent to the treated surface was performed with a scanning electron microscope JEOL JXA-8200. The typical image of the irradiated surface of tungsten is shown in Fig. 1. There is a quasi-periodic system of bands with the period ~0.5 μm, which remains constant throughout the treated area.
However, you may notice that sometimes the band breaks (indicated by arrows in Fig. 1) with the corresponding deformation of the bands around, while the distance between the bands remains unchanged. Thus, dislocations occur in the system of bands. As noted above, the obtained system of bands on the surface is most logically explained as the result of interference of the incident and surface waves (surface plasmon polariton in the case of metals). In this case, disappearance of the interference fringe indicates the change of the phase difference of the interfering waves by 2π when going around this point, i.e. the presence of the screw dislocation of the wavefront of one of the waves – the optical vortex. These dislocations in the interference pattern with vortex beams are well known [8].
Similar structures were obtained on metals (W, Mo, Ta, Ni, Ag, Pt). Preliminary experiments showed that these structures are observed also on the surface of semiconductors (Si for example).
Noteworthy is that in the stripes and between them spherical shape nanostructures with the size ~30…100 nm are present (Fig. 2).
Fig. 1. Characteristic “forks” associated with the presence of “optical vortices” in electromagnetic fields taking part in formation of structures on the surface of tungsten.
Fig. 2. Image of treated tungsten surface with larger magnification reveals nanostructures in the stripes and between them.
3. Results and discussion
The beams with helical wavefront perturbations (singular beams) occupy a special place among the wave beams with a variable structure of the amplitude-phase profile. This kind of disturbance causes the vortex nature of the propagating light energy, which suggests the existence of peculiar optical vortices [9].
To generate singular optical beams, most widely used are the methods for direct conversion of the spatially inhomogeneous phase of the light wave and holographic interferometry methods of converting light beams. In the first case, spiral phase plates or liquid crystal spatial modulators are used. Another method to generate singular beams is diffraction of the initial Gaussian beam on special optical transparencies based on computer-generated holograms [9].
Finally, we discuss briefly a possible mechanism of formation of optical vortices when the metal surface is irradiated by power femtosecond pulses.
Under “natural conditions”, most of the wavefront dislocations of laser beams that cause the vortex structure of the light field are observed in the scattering of light by random media on the propagation path (for example, when passing sufficiently large tract in the atmosphere or scattering on very rough surfaces).
It is known that during irradiation of rough surfaces with laser, speckles appear. In [10], it is pointed out for the first time that the wavefront dislocations are inherent to optical fields that have a speckle structure. For monochromatic polarized beam with sufficiently developed inhomogeneities of complex amplitude, appearance of wavefront dislocations is inevitable [10].
When discussing the possible mechanism of formation of optical vortices as a result of power laser pulse interaction with the metal surface, note the similarity of the resulting fringe pattern on the metal surface with the transparencies used to produce beams with vortices. Besides, as formation of the structures on the surface occurs gradually, there takes place an accumulation effect of sequential exposure from hundreds or thousands of pulses. The surface of metal may be not only a recording medium, but it can also participate in formation of spatial distribution of the amplitude and phase of the wavefront, i.e. operate as a space-phase modulator. We can assume that initially small surface roughnesses are minor points forming wavefront dislocations, which then as a result of interference with the incident plane wave form a quasi-periodic structure with dislocation that in turn acts as a phase modulator and so on. Thus, a positive feedback in the system is realized as a result of formation of a distinct stable self-consistent structure under the action of laser pulses.
4. Conclusion
The study of periodic structures formed on the surface of metals and semiconductors under irradiation with femtosecond laser pulses showed characteristic quasi-periodic patterns with dislocations (broken stripes). The offered interpretation associates these dislocations in interference pattern with the presence of wavefront dislocations – optical vortices on the surface or scattered waves. Most distinct structures were observed on the surface of tungsten, which is probably due to its high melting point.
Acknowledgements
The authors thank V.B. Sobolev (Technical Center NAS of Ukraine) for carrying out electron microscopy of the samples. Partial financial support came from Ukrainian State target scientific and technical program (Nanotechnologies and Nanomaterials( for 2010-2014 project No. 1.1.3.11, 3.5.5.23.
References
1. D.C. Emmony, R.P. Howson, and L.J. Willis, Laser mirror damage in germanium at 10.6 (m // Appl. Phys. Lett. 23, p. 598-600 (1973).
2. Zhou Guosheng, P.M. Fauchet, and A.E. Siegman, Growth of spontaneous periodic surface structures on solids during laser illumination // Phys. Rev. B, 26(10), p. 5366-5381 (1982).
3. J.F. Young, J.S. Preston, H.M. van Driel, and J.E. Sipe, Laser-induced periodic surface structure. II. Experiments on Ge, Si, Al, and brass // Phys. Rev. B, 27(2), p. 1155-1172 (1983).
4.
Kiminori Okamuro, Masaki Hashida, Yasuhiro Miyasaka, Yoshinobu Ikuta, Shigeki Tokita, and Shuji Sakabe, Laser fluence dependence of periodic grating structures formed on metal surfaces under femtosecond laser pulse irradiation // Phys. Rev. B, 82, p. 165417-5 (2010).
5. Litao Qi, Kazuhiro Nishii, and Yoshiharu Namba, Regular subwavelength surface structures induced by femtosecond laser pulses on stainless steel // Opt. Lett. 34(12), p. 1846-1848 (2009).
6. T. Sano, M. Yanai, E. Ohmura, Y. Nomura, I. Miyamoto, A. Hirose, K. Kobayashi, Femtosecond laser fabrication of microspike-arrays on tungsten surface // Appl. Surf. Sci. 247, p. 340-346 (2005).
7. S.R.J. Brueck and D.J. Ehrlich, Stimulated surface-plasma-wave scattering and growth of a periodic structure in laser-photodeposited metal films // Phys. Rev. Lett. 48(24), p. 1678-1681 (1982).
8. L.A. Kazak, A.L. Tolstik, Formation of superposition and stability of vortex optical beams of different orders // Vestnik Belorusskogo Gosudarstv. Universiteta, Ser. 1, №2, p. 3-7 (2010), in Russian.
9. M. Padgett, J. Courtial, L. Allen, Light’s orbital angular momentum // Physics Today, 57(5), p. 35-40 (2004).
10. N.B. Baranova, B.J. Zeldovich, A.B. Mamaev, N.F. Pilipetskii, V.V. Shkunov, Wavefront dislocations of speckle-inhomogeneous field (theory and experiment) // JETP Lett. 33(4), p. 206-210 (1981), in Russian.
© 2014, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
165
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