arXiv subjects

A. M. Shegeda

Publications and source records attributed to A. M. Shegeda.

4 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↗

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↗