Active Electric Dipole Energy Sources: Transduction via Electric Scalar and Vector Potentials

Abstract

The creation of electromagnetic energy may be realised by engineering a device with a method of transduction, which allows an external energy source, such as mechanical, chemical, nuclear, etc., to be impressed into the electromagnetic system through a mechanism that enables the separation of opposite polarity charges. For example, a voltage generator, such as a triboelectric nanogenerator, enables the separation of charges through the transduction of mechanical energy, creating an active physical dipole in the static case, or an active Hertzian dipole in the time-dependent case. The net result is the creation of a static or time-dependent permanent polarisation, respectively, without an applied electric field and with a non-zero vector curl. This system is the dual of a magnetic solenoid or permanent magnet excited by a circulating electrical current or fictitious bound current, respectively, which supplies a magnetomotive force described by a magnetic vector potential and a magnetic geometric phase proportional to the enclosed magnetic flux. Thus, the active electric dipole voltage generator has been described macroscopically by a circulating fictitious magnetic current boundary source and exhibits an electric vector potential with an electric geometric phase proportional to the enclosed electric flux density. This macroscopic description of an active dipole is a semi-classical average description of some underlying microscopic physics, which exhibits emergent nonconservative behaviour not found in classical closed-system laws of electrodynamics. We show that the electromotive force produced by an active dipole in general has both electric scalar and vector potential components to account for the magnitude of the electromotive force it produces. Independent of the electromagnetic gauge, we show that Faraday’s and Ampere’s law may be derived from the time rate of change of the magnetic and dual electric geometric phases. Finally, we analyse an active cylindrical dipole in terms of scalar and vector potential and confirm that the electromotive force produced, and hence potential difference across the terminals is a combination of vector and scalar potential difference depending on the aspect ratio (AR) of the dipole. For long thin active dipoles (AR approaches 0), the electric field is suppressed inside, and the voltage is determined mainly by the electric vector potential. For large flat active dipoles (AR approaches infinity), the electric flux density is suppressed inside, and the voltage is mainly determined by the scalar potential.

Sensitivity of Resonant Axion Haloscopes to Quantum Electromagnetodynamics

“…The opposite sign convention is used to keep them consistent with how the auxiliary fields ($$\vec{D}$$ and $$\vec{H}$$) are defined in matter, which then may be generalized to $$$$\begin{equation} \begin{aligned} \vec{D}_1=\epsilon _0\vec{E}_1+\vec{P}_{e1}+\vec{P}_{m1} =\epsilon _0\vec{E}_1-(g_{a \gamma \gamma } +g_{a BB})a\epsilon _0c\vec{B}_{0},\nobreakspace \text{and} \\ \vec{H}_1=\frac{1}{\mu _0}\vec{B}_1-\vec{M}_{e1}-\vec{M}_{m1}=\frac{1}{\mu _0}\vec{B}_1+(g_{a \gamma \gamma } +g_{a BB})a\epsilon _0c \vec{E}_{0} \end{aligned} \end{equation}$$$$Note in this representation of axion‐modified electrodynamics, both the electric field and magnetic flux densities may have both vector and scalar potentials as dictated by two potential theory. [ 20,21,26–33 ] One can also write these electrodynamic equations in terms of the auxiliary fields. Thus, assuming $$\vec{\nabla }a=0$$ and combin...…”

“…Note in this representation of axion-modified electrodynamics, both the electric field and magnetic flux densities may have both vector and scalar potentials as dictated by two potential theory. [20,21,[26][27][28][29][30][31][32][33] One can also write these electrodynamic equations in terms of the auxiliary fields. Thus, assuming ⃗ ∇a = 0 and combining ( 18) with ( 6)-( 9), we may write the axion-modified electrodynamics as…”

Quantifying Output Power and Dynamic Charge Distribution in Sliding Mode Freestanding Triboelectric Nanogenerator

“…In general, the force due to the external energy source acts on each free and bound charge which provides a non‐conservative electromotive force, finally producing electricity. [ 11–13 ]…”

“…[ 11–13 ] Regarding the former as an ideal voltage generator or battery produces a direct current (dc) voltage and an electric field directly, the force per unit charge due to the external energy source enables the electrons to move in the opposite direction, realizing the separation of opposite polarity charges within the voltage source. [ 11–14 ] The non‐electric energy source provides a force on the electric charges which requires generalization of the constitutive relations and results in a modification of Maxwell's equations. [ 11,12 ] The above approach has been utilized to investigate the dc bound‐charge voltage source which is essentially a bar electret.…”

“…[ 11–14 ] The non‐electric energy source provides a force on the electric charges which requires generalization of the constitutive relations and results in a modification of Maxwell's equations. [ 11,12 ] The above approach has been utilized to investigate the dc bound‐charge voltage source which is essentially a bar electret. [ 15–18 ] The electret exhibits a quasi‐permanent electric field due to its macroscopic polarization; and it is overall electrically neutral.…”