Influence of Thermocycling on the Polarization Distribution of Doped SBN Crystals

Abstract

Influence of thermocycling on the polarization state in the SBN crystals doped with Eu or Rh was examined. The polarization depth profile was controlled by measuring the depth dependence of the pyroelectric coefficient by Thermal Square Wave method. The switching processes were studied using the thermal Barkhausen effect method. It has been shown that heating/cooling cycle results in essential depolarization of both studied materials.

Physical and Mathematical Models of Quantum Dielectric Relaxation in Electrical and Optoelectric Elements Based on Hydrogen-Bonded Crystals

“…[2,9]. The methods of the quantum theory of proton conductivity have a direct application to theoretical and applied studies of quantum transitions of protons in the hydrogen sublattice during the formation of spontaneous polarization in ferroelectric crystals with hydrogen bonds (KDP) near the second-order phase transition point [3][4][5][6][7][8]. The results of the research, in the future, will find application in the field of laser technology and nonlinear optics, in particular, in studying the effects of quantum proton tunneling on second-order nonlinear optical processes (second harmonic generation, parametric generation and amplification of light, frequency mixing, electro-optical effect)and nonlinearity of a higher order in the frequency of the electromagnetic field (the effect of self-action of laser radiation), which is important for the technique of femtosecond lasers [24][25][26][27][28].…”

“…ξψ n (ξ)cos πma d ξ dξ, where the wave functions ψ n (ξ) are taken for a model of particle motion in a one-dimensional field a potential pit with spatial-periodic potential relief within the pit and infinitely high edge walls U max → ∞ . Internal potential barriers and potential pits are taken by parabolic shape, a calculation quasi-discreet the energy spectrum of particles (protons) is performed for the blocking electrode model U max → ∞ , when ψ n (0) = 0, ψ n (0) = 0, according to the scheme outlined in [8].…”

“…Going back to the original u n,1 (ξ; τ) = ∑ ∞ m=1 U n,1 (m; τ) × cos πma d ξ , assumptions in (5) taking into account and notation, we construct the desired scalar function u n (ξ; τ) = ς 0 u n,1 (ξ; τ) describing relaxation motion of protons with energies of the unperturbed spectrum E (0) n [8] in crystal, perturbed by the electric field E(x; t) = E 0 exp(iωt) with blocking electrodes…”

“…A separate category of ion-molecular dielectrics is represented by hydrogen-bonded crystals (HBC) used in radio electronics (elements of electronically controlled systems of microwave, ultra-high frequency [6]); optoelectronics and nonlinear optics (nonlinear optical signal converters; high-precision long-mode fiber optic strain gauges in solid-state elements of structures and structures in mining and construction technologies); laser technology (regulators of radiation parameters and electric shutters (KDP (potassium dihydrogenphosphate)) [7][8][9]; microelectronics (field effect transistors, resonant tunnel diodes, MIS, MSM structures); electrochemical technologies (solid-state fuel cells based on dielectrics with high ionic conductivity) [10][11][12][13][14].…”