V. I. Balykin

Single nano-hole as a new effective nonlinear element for third-harmonic generation

In this letter, we report on a particularly strong optical nonlinearity at the nanometer scale in aluminum. A strong optical nonlinearity of the third order was demonstrated on a single nanoslit. Single nanoslits of different aspect ratio were excited by a laser pulse (120xa0fs) at the wavelength 1.5xa0μm, leading predominantly to third-harmonic generation (THG). It has been shown that strong surface plasmon resonance in a nanoslit allows the realization of an effective nanolocalized source of third-harmonic radiation. We show also that a nanoslit in a metal film has a significant advantage in nonlinear processes over its Babinet complementary nanostructure (nanorod): the effective abstraction of heat in a film with a slit makes it possible to use much higher laser radiation intensities.

Atom "Pinhole Camera" with Nanometer Resolution

An atom “pinhole camera” with nanometer resolution has been experimentally implemented for the first time. Owing to the use of this camera, an array of ∼106 identical nanostructures of Cr atoms with a characteristic size of the nanostructure of less than 50 nm has been created on a glass surface. Nanostructures of arbitrary shapes have been created.

Atom nanooptics based on photon dots and photon holes

New types of light fields localized in nanometer-sized regions of space were observed and analyzed. The possibility of using these nanolocalized fields in atom optics for atom focusing and localization is discussed.

Laser-induced quantum adsorption of atoms on a surface

A method of the quantum adsorption of atoms on a surface is proposed and experimentally implemented. The loading of atoms into a surface potential well (adsorption) occurs due to the loss of kinetic energy in the process of the inelastic collision of two laser-excited atoms. This scheme is implemented for Rb atoms adsorbed on the surface of a YAG crystal. The possibility of producing microstructures of arbitrary shape that consist of atoms localized on the dielectric surface is also demonstrated.

Motion of an atom under the effect of femtosecond laser pulses : From chaos to spatial localization

The spatial localization of an atom in a field of periodic femtosecond laser pulses is considered. It has been shown that the atom can be localized with absolute accuracy in the nanometer range. The time interval during which the atom is situated in the laser field is only 10−7–10−8 of the total localization time interval.

Nanoscale and femtosecond optical autocorrelator based on a single plasmonic nanostructure

We demonstrated a nanoscale size, ultrafast and multiorder optical autocorrelator with a single plasmonic nanostructure for measuring the spatio-temporal dynamics of femtosecond laser light. As a nanostructure, we use a split hole resonator (SHR), which was made in an aluminium nanofilm. The Al material yields the fastest response time (100?as). The SHR nanostructure ensures a high nonlinear optical efficiency of the interaction with laser radiation, which leads to (1) the second, (2) the third harmonics generation and (3) the multiphoton luminescence, which, in turn, are used to perform multi-order autocorrelation measurements. The nano-sized SHR makes it possible to conduct autocorrelation measurements (i) with a subwavelength spatial resolution and (ii) with no significant influence on the duration of the laser pulse. The time response realized by the SHR nanostructure is about 10?fs.

Focusing of an atomic beam by a two-dimensional magneto-optical trap

A method for focusing neutral atoms based on the light-pressure force in a nonuniform magnetic field is proposed and analyzed. Its particular scheme is realized by means of a two-dimensional magneto-optical trap using a thermal beam of Rb atoms. A feature of this focusing method is the linear dependence of the focal length on the longitudinal velocity of atoms in contrast to the quadratic dependence in the known methods of focusing material-particle beams. The minimum size of the waist of the focused atomic beam is equal to 270 µm. Owing to focusing by means of the two-dimensional magneto-optical trap, the velocity monochromatization of a thermal atomic beam is realized: the width of the distribution of the longitudinal atomic velocities in the beam is reduced from 350 to 60 m/s.

Control of SPP propagation and focusing through scattering from nanostructures

Measuring the characteristics of radiation scattered by surface plasmon polariton waves and detecting them in the far field is the only efficient method for studying the directivity of propagation, wave vector magnitude, and propagation length of such waves. In the present work, we demonstrate that it is possible to control the properties of surface plasmon polaritons propagating along the surface of metal nanofilms by scattering from nanoobjects, namely, nanogrooves and nanopits, formed in the nanofilms. It is shown that this technique allows the main parameters of surface plasmon polaritons to be measured.

A nanohole in a thin metal film as an efficient nonlinear optical element

The nonlinear optical properties of single nanoholes and nanoslits fabricated in gold and aluminum nanofilms are studied by third harmonic generation (THG). It is shown that the extremely high third-order optical susceptibility of aluminum and the presence of strong plasmon resonance of a single nanohole in an aluminum film make possible an efficient nanolocalized radiation source at the third harmonic frequency. The THG efficiency for a single nanohole in a thin metal film can be close to unity for an exciting laser radiation intensity on the order of 1013 W/cm2.

Diffraction-Limited Focusing of Plasmonic Wave by a Parabolic Mirror

We demonstrate effective, up to 30%, reflection of the surface plasmon-polariton wave (SPP) from a nanogroove made on Ag film surface. The use of SPP reflection from a nanogroove having a shape of parabola helps to realize a new element in nanoplasmonics—parabolic SPP mirror. It was found that the mirror allows focusing of the SPP into a diffraction-limited spot with a lateral size of about λSPP (λSPPu2009=u2009800xa0nm—SPP wavelength). The possibility of spatial scanning the focusing spot of SPP on the surface of Ag film is shown.