High electric field conduction in low-alkali boroaluminosilicate glass

Abstract

Electrical conduction in silica-based glasses under a low electric field is dominated by high mobility ions such as sodium, and there is a transition from ionic transport to electronic transport as the electric field exceeds 108 V/m at low temperatures. Electrical conduction under a high electric field was investigated in thin low-alkali boroaluminosilicate glass samples, showing nonlinear conduction with the current density scaling approximately with E1/2, where E is the electric field. In addition, thermally stimulated depolarization current (TSDC) characterization was carried out on room-temperature electrically poled glass samples, and an anomalous discharging current flowing in the same direction as the charging current was observed. High electric field conduction and TSDC results led to the conclusion that Poole-Frenkel based electronic transport occurs in the mobile-cation-depleted region adjacent to the anode, and accounts for the observed anomalous current.

Structural Designs of Transparent Polyimide Films with Low Dielectric Properties and Low Water Absorption: A Review

“…The dielectric performance of a material is measured in terms of electrostatic energy storage and loss in the presence of an electric field and is expressed in terms of its dielectric constant and dielectric loss [ 37 , 38 , 39 ], which are important parameters used to evaluate the electrical insulating performance of a material. The dielectric properties of any dielectric material are well known to mainly depend on internal factors, including various types of polarization phenomena, and external factors, such as frequency, temperature, and humidity [ 40 ]. Electric dipoles are created in an external electric field as electrons shift with respect to the atomic nuclei as centroid electron clouds depart from their centroid nuclei.…”

“…Electronic polarization occurs when the electron cloud surrounding an atom is displaced with respect to the nucleus in an external electric field. A significant amount of energy is required to excite and establish resonance at electric field frequencies between 10 8 and 10 10 MHz (UV–visible range) because nuclei and electrons interact strongly [ 40 ]. In contrast, atomic polarization results from molecular skeletal deformations in an external electric field, which is the dominant polarization mode that affects the dielectric constant, despite its smallness (only one-tenth of the magnitude of electronic polarization); it appears at infrared frequencies between 10 4 and 10 6 MHz [ 42 ].…”

“…Orientational and space-charge polarizations have smaller effects and are considered to be relaxing polarizations. Orientational polarization is observed in covalent molecules with permanent dipole moments, where dipoles are aligned with the electric field [ 40 ]. This type of polarizability typically depends on the temperature and decreases with increasing temperature; it is excitable at radio frequencies in the 10 −9 to 10 −6 MHz range.…”

“…There a four types (Figure 1) of polarization mechanisms: (a) induced or electronic polarization, atomic polarization, (c) orientation polarization, and (d) interfacial or space-charge pola zation [41]. Here, electronic and atomic polarizations are resonance effects that are ind pendent of temperature, whereas orientation polarization and space-charge polarization relaxation effects that mainly depend on temperature [40]. Frequency is an important external factor that influences the dielectric constant.…”