arXiv subjects

V. I. Balykin

Publications and source records attributed to V. I. Balykin.

7 recordsLinked to original sources

arXiv2018

Plasmonic sensor based on the Ebbesen effect

We present a new method for measuring low concentrations and simultaneously small volumes of fluorescent molecules based on the use of the Ebbesen effect of the extraordinary transmission (EOT) of light through an array of nano-holes. In the method the EOT effect is realized at the fluorescence wavelength of the detected molecules with a low transmission of light at the absorption wavelength. The approach allows realizing high level of the sensor sensitivity due to suppression of the inevitable parasitic luminescence of the sensor substrate. The method was demonstrated by detecting an ultra low concentration (at a level of 20 pg/ml (3 p.p.t.)) and an ultra-small volume (about 5 μl) of Cy-5 fluorescent markers in a dimethyl sulfoxide solution.

physics.app-ph↗

arXiv2006

Optical Nanofibers for Manipulating and Probing Single-Atom Fluorescence

We demonstrate how optical nanofibers can be used to manipulate and probe single-atom fluorescence. We show that fluorescence photons from a very small number of atoms, average atom number of less than 0.1, around the nanofiber can readily be observed through single-mode optical fiber under resonant laser irradiation. We show also that optical nanofibers enable us to probe the van der Waals interaction between atoms and surface with high precision by observing the fluorescence excitation spectrum.

quant-ph↗

arXiv2004

State-insensitive trapping and guiding of cesium atoms using a two-color evanescent field around a subwavelength-diameter fiber

We calculate the optical potentials, i.e. the light shifts, of the ground and excited states of atomic cesium in a two-color evanescent field around a subwavelength-diameter fiber. We show that the light shifts of the $6S_{1/2}\leftrightarrow 6P_{3/2}$ transitions can be minimized by tuning one trapping light to around 934.5 nm in wavelength (central red-detuned magic wavelength) and the other light to around 685.5 nm in wavelength (central blue-detuned magic wavelength). The simultaneous use of the red- and blue-detuned magic wavelengths allows state-insensitive two-color trapping and guiding of cesium atoms along the thin fiber. Our results can be used to efficiently load a two-color dipole trap by cesium atoms from a magneto-optical trap and to perform continuous observations.

quant-ph↗

arXiv2004

Field intensity distributions and polarization orientations in a vacuum-clad subwavelength-diameter optical fiber

We study the properties of the field in the fundamental mode HE$_{11}$ of a vacuum-clad \textit{subwavelength-diameter} optical fiber using the exact solutions of Maxwell's equations. We obtain simple analytical expressions for the total intensity of the electric field. We discuss the origin of the deviations of the exact fundamental mode HE$_{11}$ from the approximate mode LP$_{01}$. We show that the thin thickness of the fiber and the high contrast between the refractive indices of the silica core and the vacuum clad substantially modify the intensity distributions and the polarization properties of the field and its components, especially in the vicinity of the fiber surface. One of the promising applications of the field around the subwavelength-diameter fiber is trapping and guiding of atoms by the optical force of the evanescent field.

quant-ph↗

arXiv2004

Atom waveguide using a two-color evanescent light field around a subwavelength-diameter optical fiber

We suggest using a two-color evanescent light field around a subwavelength-diameter fiber to trap and guide atoms. The optical fiber carries a red-detuned light and a blue-detuned light, with both modes far from resonance. When both input light fields are circularly polarized, a set of trapping minima of the total potential in the transverse plane is formed as a ring around the fiber. This design allows confinement of atoms to a cylindrical shell around the fiber. When one or both of the input light fields are linearly polarized, the total potential has two local minimum points in the transverse plane. This design allows confinement of atoms to two straight lines parallel to the fiber axis. Due to the thin thickness of the fiber, we can use far-off-resonance fields with substantially differing evanescent decay lengths to produce a net potential with a large depth, a large coherence time, and a large trap lifetime. For example, a 0.2-$μ$m-radius silica fiber carrying 30 mW of 1.06-$μ$m-wavelength light and 29 mW of 700-nm-wavelength light, both fields are circularly polarized at the input, gives for cesium atoms a trap depth of 2.9 mK, a coherence time of 32 ms, and a recoil-heating-limited trap lifetime of 541 s.

quant-ph↗

arXiv2004

Atom trapping and guiding with a subwavelength-diameter optical fiber

We suggest using an evanescent wave around a thin fiber to trap atoms. We show that the gradient force of a red-detuned evanescent-wave field in the fundamental mode of a silica fiber can balance the centrifugal force when the fiber diameter is about two times smaller than the wavelength of the light and the component of the angular momentum of the atoms along the fiber axis is in an appropriate range. As an example, the system should be realizable for Cesium atoms at a temperature of less than 0.29 mK using a silica fiber with a radius of 0.2 $μ$m and a 1.3-$μ$m-wavelength light with a power of about 27 mW.

physics.optics↗

arXiv2003

Atom Nanooptics Based on Photon Dots and Photon Holes

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

quant-ph↗