arXiv subjects

V. N. Lisin

Publications and source records attributed to V. N. Lisin.

7 recordsLinked to original sources

arXiv2018

Stark shift in Y 2 SiO 5 :Er 3+ by the photon echo beating method

The Stark coefficient of the Er 3+ ion in Y 2 SiO 5 is determined for transition). The stark photon echo beating method (SPEB) was used: the pseudo-Stark frequency shift was measured from the period of beats of the temporal form of the photon echo signal. Light beatings were caused by the use of a weak electric field pulse that splits the frequencies of optical transitions of nonequivalent subgroups of echo-active Er 3+ ions in Y 2 SiO5

cond-mat.mtrl-sci↗

arXiv2016

The application of the weak electric field pulse to measure the pseudo-Stark split by the photon echo beating

A novel scheme for determining the pseudo-Stark splitting of optical lines has been suggested and tested in experiment. The scheme allows one to observe the beating of a photon echo waveform under conditions of overlap in time between a weak electric pulse and its echo- pulse. The pseudo-Stark splitting is equal to the inverse average modulation period of the echo waveform. The photon echo beating of the R1-line in Ruby has been observed. The dependence of the inverse average modulation period of the echo waveform on the average value of the electric field over the optically excited volume has been found. The obtained values of the pseudo-Stark parameter are in good agreement with known literature data.

cond-mat.mes-hall↗

arXiv2014

Measurement of g-factors of ground and excited optical states of Er3+ in YLiF4 and LuLiF4 in zero dc magnetic field by photon echo method

New scheme of definition of g-factors as ground as excited optical states of a paramagnetic ion in zero external constant magnetic field has been proposed and experimentally realized in optical systems in which Zeeman Effect is manifested. A pulse of a weak magnetic field leads to occurrence of relative phase shifts of the excited dipoles and, as consequence, to modulation of a photon echo waveform if magnetic pulse (MP) overlaps in time with echo-pulse. The modulation periods of the waveform depend on polarization of the laser light, which excites the photon echo. The values of these periods for σ- and π- laser light polarization have been measured and then the g-factors of the ground 4I15/2 and excited 4F9/2 states of the Er3+ ion in the LuLiF4 and the YLiF4 matrices have been determined. Values of the g-factors have been compared with the known literary data.

cond-mat.mtrl-sci↗

arXiv2010

Ballistic and Diffuse Electron Transport in Nanocontacts of Magnetics

The transition from the ballistic electron transport to the diffuse one is experimentally observed in the study of the magnetic phase transition in Ni nanocontacts with different sizes. It is shown that the voltage $U_C$ needed for Joule heating of the near-contact region to the critical temperature does not depend on the contact size only in the diffuse mode. For the ballistic contact it increases with decrease in the nanocontact size. The reduction of the transport electron mean free path due to heating of NCs may result in change of the electron transport mode from ballistic to diffusive one.

cond-mat.mes-hall↗

arXiv2010

Current-induced phase transition in ballistic Ni nanocontacts

Local phase transition from ferromagnetic to paramagnetic state in the region of the ballistic Ni nanocontacts (NCs) has been experimentally observed. We found that contact size reduction leads to an increase in the bias voltage at which the local phase transition occurs. Presented theoretical interpretation of this phenomena takes into the account the specificity of the local heating of the ballistic NC and describes the electron's energy relaxation dependences on the applied voltage. The experimental data are in good qualitative and quantitative agreement with the theory proposed.

cond-mat.mes-hall↗

arXiv2003

Time-resolved Photo-Phonon Spectroscopy of Exchange Coupled ${Cr^{3+}}$ - Pairs in Ruby

A rather simple method is used to detect at once both optical absorption spectra and excited-states nonradiative transitions in 0,03 at ${%}$ and 0,16 at ${%}$ ruby at temperature 2 K. The technique utilizes a time-resolved bolometer detection of phonons, generated by the excited-state nonradiative relaxation following optical excitation with a pulsed tunable dye laser. The observed excitation spectra of phonons well coincide with already known absorption spectra of both single chromium ions and pairs of the nearest neighbors. For the first time the fast ($\leqslant 0,5 μs$)resonant energy transfer from single chromium ions to the fourth- nearest neighbors is observed directly. The new strongly perturbed $Cr$-single-ion sites are observed.

cond-mat.mtrl-sci↗

arXiv2001

Vector Area Theorem mapping in crystals and polarization stability of SIT-solitons

The stability of polarization, areas, and number of self-induced transparency (SIT)-solitons at the output from the LaF_3:Pr^{3+} crystal is theoretically studied versus the polarization direction and the area of the input linearly polarized laser pulse. For this purpose the Vector Area Theorem is rederived and two-dimensional Vector Area Theorem map is obtained. The map is governed by the crystal symmetry and takes into account directions of the dipole matrix element vectors of the different site subgroups of optically excited ions. The Vector Area Theorem mapping of the time evolution of the laser pulse allows one to highlight soliton polarization properties.

physics.optics↗