Research Areas
Nanophotonics & Nanoplasmonics
Publications
News
Atom Femto Trap
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A new paper has been published in Applied Physics B. In this work, we demonstrate the trapping of rubidium (Rb) atoms in a pulsed optical dipole trap formed by femtosecond laser radiation with a pulse duration as small as 70 fs. The atom localization in such trap strongly depends on the heating of the atoms caused by the momentum diffusion due to the dipole force fluctuations. The atom femto traps can be used for localization of atoms others than alkaline and alkaline earth atomic elements by conversation of pulsed laser radiation of visible or near infrared to UV spectral.. |
Plasmonic nanolaser for intracavity spectroscopy and sensorics
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We demonstrated
intracavity plasmonic laser spectroscopy using a plasmonic laser
created from a periodically perforated silver film with a liquid gain
medium. An active zone of the laser is formed by a highly elongated
spot of pumping. This results in a significantly more efficient
diffusive
mixing of dye molecules, which suppresses the effect of their
bleaching, and in the ability to reduce the volume of the gain medium
to as little as 400 nl. We use this design for a stable plasmonic laser
in multiple measurements and demonstrate that it is highly effective as
a spaser spectroscopy sensor for intracavity detection of an absorptive
dye at 0.07 ppm. This work provides an opportunity to
develop applications of intracavity plasmonic laser spectroscopy in
biological label detection and other fields. |
Femtosecond plasmon interferometer
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A new paper has been published in Optics Communications. We have realized a plasmonic interferometer formed by a nanoslit and a nanogroove in a single-crystal gold film. The possibility of measuring laser pulses of ultimately short durations, corresponding to two periods of a light wave (6 fs pulse duration), has been demonstrated using this interferometer. |
Single photon transport by a moving atom
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A new paper has been published in New Journal of Physics. This work we have proposed and investigated for the first time an efficient way of photon transport through a subwavelength hole by a moving atom. The transfer mechanism is based on the reduction of the wave packet of a single photon due to its absorption by an atom and, correspondingly, its localization in a volume is smaller than both the radiation wavelength and the nanohole size. The scheme realizes the transformation of a single-photon single-mode wave packet of the laser light into a single-photon multimode wave packet in free space. |  |
Split Hole Resonator: A Nanoscale UV Light Source
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A new paper
has been published in Nano Letters. This work presents results of
investigation of nonlinear optical interaction with a single
gold nanostructure, the split-hole resonator (SHR) under the
state-of-the-art experimentally realized conditions. To realize
interaction with all spectral components of a 6 fs laser pulse
several multipole plasmon resonances were simultaneously
excited in the SHR nanostructure. To the best of our knowledge, this
paper reports for the first time a strong nonlinear optical
interaction at the frequencies of these resonances that leads to (i)
the second harmonic generation, (ii) the third harmonic
generation (THG), and (iii) the light generation at mixed frequencies.
The THG near field amplitude reaches 0.6% of the
fundamental frequency field amplitude, which enables the creation of UV
radiation sources with a record high intensity. The UV
THG may find many important applications including biomedical ones (such
as cancer therapy). |
Optical Tamm state and giant asymmetry of light transmission through an array of nanoholes
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A new paper
has been published in
Physical Review A. In this work, We have predicted theoretically and
verified experimentally the occurrence of a giant asymmetry of the
transmission of arbitrarily polarized light propagating through a
linear nonmagnetic optical system that consists
of a metal film with a two-dimensional array of nanoholes in it and
that is deposited on the surface of a planar
dielectric photonic crystal. The asymmetry of the light transmission is
caused by two factors: (i) the excitation of
an optical Tamm state in the system, and (ii) the existence of many
secondary lobes in the diffraction pattern. Our
results are of interest for the development of efficient planar optical
diodelike systems and related nanophotonic
devices. |
Optical Tamm state on a femtosecond time scale
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A new paper
has been published in
Physical Review A. In this work, we investigated the temporal dynamics
of the optical Tamm state (OTS) that arises at the interface
between a one-dimensional photonic crystal and a gold nanofilm. The
temporal dynamics was measured by two
methods: (1) the spectral method, which is based on the analysis of the
spectral composition of reflected light, and
(2) the probe method, i.e., by embedding an inertialess probe into the
OTS mode. It was found that the temporal
dynamics of OTS formation is determined by the quality factor of the
photonic-crystal/nanofilm microcavity with
a characteristic time of OTS formation in the range of 100 to 300 fs. |
Optical Tamm state and extraordinary light transmission through a nanoaperture
 Fig.1  Fig.2 |
A new paper has been published in
Physical Review A. The effect of an extraordinary transmission (ET) of
light
through an array of nanoapertures has been observed for the first time
by Ebbesen et al. The effect describes the light transmission
through a nanoaperture array, which is considerably higher than
predicted by the Bethe-Bouwkamp theory. The ET effect is due to the
excitation of propagating plasmons. We have shown another way to enhance transmission through a nanoaperture: due to the appearance of an optical Tamm state field at the interface of the planar structure “metamaterial–metal-film with hole”, Fig.1 (a). The 28-fold enhanced transmission of light through a single nanohole in Au film has been experimentally demonstrated. Moreover we have shown theoretically that this enhancement can be as large as 800% to the light flux incident on the aperture with an optimal cross section, Fig.2. |
Subwavelength light localization based on optical nonlinearity and light polarization
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A new paper has been published in Optics Letters. An SHR can be also considered as a nanolocalized radiation source. From this viewpoint, the SHR has a number of merits in compare with other nanostructures. First, there is no accompanying background of the excitation radiation (which is very high with nanoparticles). Second, the transmission of the radiation through the is significantly higher than through the nanohole of the same size. Third, since the SHR is created in a metal film, it is capable of withstanding a higher intensity of the radiation incident on it than isolated nanoparticles, and, correspondingly, as a nonlinear element, can be more efficient. |
Giant optical nonlinearity of a single plasmonic nanostructure
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A new paper has been published in Optics Express. We realize giant optical nonlinearity of a single plasmonic nanostructure - a Split Hole Resonator (SHR). We demonstrate the use of SHR as highly effective nonlinear optical element for: (1) generation of third harmonic from a single SHR and (2) efficient multiphoton luminescence from a single SHR.SHR nanostructure formed in aluminum film. On the Figure below: (a) an electron microscope image of the nanostructure formed by a nanohole of 380 nm diameter and nanorod of 220 nm (length) × 120 nm (width), (b) calculated enhancement of the electric field amplitude upon irradiation of the nanostructure of Figure (a) by a plane monochromatic wave with a wavelength of 1560 nm, (c) an optical image of the nanostructure upon its laser irradiation at a wavelength of 1560 nm and detection at the THG wavelength, and (d) measured spectrum of radiation that forms optical image presented on Figure (c). The incident radiation is polarized along the direction of the nanorod of the nanostructure. |
Proposed a new element for nanooptics and nanoplasmonics: Split Hole Resonator (SHR)
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We propose and experimentally realize a new element for nanoplasmonics which we call a Split Hole Resonator (SHR). The SHR is the marriage of two basic elements of nanoplasmonics, a nanohole and a nanorod (see the Figure below). A peak field intensity in the SHR occurs at the single tip of the nanorod inside the nanohole. The peak field is much stronger than those of the nanorod and nanohole, because the SHR field involves contributions from the following two field-enhancement mechanisms: (1) the excitation of surface plasmon resonances and (2) the lightning-rod effect. We demonstrate the use of the SHR as a highly efficient nonlinear optical element for: (i) the generation of the third harmonic from a single SHR; (ii) the excitation of intense multiphoton luminescence from a single SHR; (iii) the construction of a polarization-ultrasensitive nanoelement; and finally, as a practical application, (iv) the building up of an all-optical display. |
Atom-femto trap
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A
new paper has been published in
Physical Review A. A
single atom “at
rest” is an ideal physical
object for many fundamental and applied investigations. A good
approximation is
an atom that is cooled by laser light and localized in a trap. However,
a
potential localizing the atom provides an perturbing effect on both
external
and internal degrees of freedom of the atom. The best situation is the
cooling
of the atom to a temperature corresponding to the energy of the atomic
ground
state, where the atom occupies the minimum phase space. Although the
spatial
motion of the atom is minimal in the ground state, this motion affects
the
internal degrees of freedom. Most fundamental and applied
investigations are
focused on the internal degrees of freedom. We propose and investigate approach to the minimization of the effect of the localizing field on the atom – Atom Femto Trap. Its essence is the use of the short-term and time-periodic action of the laser field on the spatial motion of a very slow atom. In such a scheme, the atom is free of the perturbing effect of the localizing field for a time interval (1 – tp / T ), where tp is the duration of the action and T is its repetition period. When femto second pulses are used, the relative time interval during which the atom is situated in the localizing field may be very short, i.e., 10 -7 -10 -6 , i.e., the atom is almost at rest. |
Institute for spectroscopy RAS, Fizicheskaya Str., 5, Troitsk, Moscow, 142190 Russia
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e-mail: atom.nano.optics@gmail.com