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2019, Electron Quantum SuperPhysics
Electronic Parameters of the 2.8 Fermi Radius Electromagnetic Standing Wave Free Electron. Magnetic Flux, Flux Density, Voltage, Current, Charge, Inductance, Capacitance, Impedance, Velocity, Frequency, Wavelength, Permeability, Permittivity and Q-Factor
The values of four different fields related to electron: gravitational, circulation, electric, and magnetic, can be written with very similar formulas that bind them in pairs: gravitational-magnetic and circulation-electric. Moreover, the four integrals over these fields in space and time produce the electron-specific 'charges': circulation quantum, rest mass, magnetic flux quantum, and elementary charge, which also form pairs analogous with respect to their proposed structure: circulation quantum-elementary charge, and rest mass-magnetic flux quantum. A specific value of the gravitational constant is hypothesized and an extension to the SI system of units is proposed allowing for comparisons between its mechanical and electromagnetic units, as was the case in the CGS-Gaussian system of units. It is hypothesized that total rest energy of electron consists in equal parts of contributions from its gravitational and electromagnetic energies.
American Journal of Physics, 1992
We study the absorption spectrum of a two-dimensional electron gas (2DEG) in a magnetic field. We find that that at low temperatures, when the 2DEG is spin polarized, the absorption spectra, which correspond to the creation of spin up or spin down electron, differ in magnitude, linewidth and filling factor dependence. We show that these differences can be explained as resulting from creation of a Mahan exciton in one case, and of a power law Fermi edge singularity in the other. The role of Coulomb interactions in the optical absorption spectrum of a Fermi sea of electrons has attracted interest for several decades. The response of the electron gas to the sudden creation of the hole attractive potential is manifested in a singularity at the photon energy for which an electron is excited to the Fermi level. This singularity, known as the Fermi edge singularity (FES), was first studied by Mahan [1, 2] in the context of the X-ray absorption edge of metals and the interband spectrum of degenerate semiconductors. Using a ladder diagram approach he was able to show that the absorption is singular at the threshold energy hω = E G + p 2 F /2µ, where E G is the gap energy, p F is the electron Fermi momentum, and µ is the electron-hole reduced mass. At higher energies, the absorption intensity decays as (ω− ω 0) −α , where α is a dimensionless coupling constant describing the interaction between the electrons and the deep hole created in the absorption process. An exact expression for the absorption spectrum was later derived by Combescot and Noziers [3, 4], and practically verified Mahan's predictions. A two-dimensional electron gas (2DEG) in modulation doped quantum wells has proven to be particularly convenient for observing and studying the FES. The ability to vary the electron density, n e , and the ratio between temperature and Fermi energy provides an important handle on the behavior of the singular-ity. Indeed, in the last two decades there has been a rich body of theoretical [5, 6, 7, 8] and experimental work [9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20] on various aspects of the singularity in this system. In particular , photoluminescence measurements have shown that the singularity persists when a magnetic field is applied [9, 18, 19]: the envelope of the Landau levels (LL) resembles the FES lineshape at zero magnetic field [8]. The role of the spin degree of freedom was, however, commonly assumed to be limited to the degeneracy in the density of states. Yet, it is plausible to expect that the 2DEG spin polarization would affect the FES in a profound way: electron-electron scattering, which plays a key role in the singularity [2], is strongly suppressed when the spin of the photo-excited electron is opposite to that of the Fermi sea electrons. In this paper we study the absorption spectrum of a high mobility 2DEG in a magnetic field. Our main finding is that at low temperatures, when the 2DEG is spin polarized, the absorption spectra which correspond to the creation of a | ↓> or | ↑> electron differ in magnitude , linewidth and filling factor dependence. We show that these differences can be explained as resulting from the creation of a Mahan exciton [1] in one case, and of a power law FES [2] in the other. Measuring the absorption spectrum of a single GaAs quantum well (QW) at low temperatures has always been a difficult task. Here we introduce a new technique for measuring the absorption spectrum of a single QW, using very weak white light in a reflection geometry. The idea is growing a cavity structure in which the QW is located at an anti-node of a standing wave formed by the optical field. The structure consists of a Bragg reflector, made of 20 pairs of λ/4 layers of AlAs and Al 0.3 Ga 0.70 As (λ = 800 nm), with its top layer is at a distance of 3λ/2 from the surface. The Bragg reflector and the sample surface form a microcavity with a broad stop-band, in which all wavelengths are back reflected (R ∼ 1). A modulation-doped GaAs QW, which is 20 nm wide and is embedded in Al 0.38 Ga 0.62 As barriers, is grown in the middle of the cavity, at a distance of 3λ/4 from the Bragg mirror and the surface. Figure 1 shows the calculated re-flectivity spectra, assuming typical excitonic parameters of a GaAs QW. The broad stop-band is seen to extend from 1.47 to 1.63 eV, with a deep notch at the exciton energy , ∼ 1.538 eV. We find that the exciton lineshape is very sensitive to the location of the QW within the cavity , and one can get a Lorentzian or dispersive lineshape by varying it [21]. The inset shows a reflectivity measurement of an optimized sample with a single modulation-doped QW at B = 9 T. It can be seen that the reflectivity at the lowest LL energy is ∼ 0.3, corresponding to an order of magnitude enhancement relative to the single pass absorption. The whole structure is grown on an n + layer that serves as a back gate. The wafer was processed to form a mesa structure, with ohmic contacts to the QW and to the back gate, such that n e can be tuned in the range (0.4 − 3) × 10 11 cm −2. The measured electron mobility is ∼ 1 × 10 6 cm 2 V −1 s −1. We used a tungsten halogen lamp to illuminate the sample, and selected a spectral range of 20 nm, centered around the heavy hole
viXra, 2014
The present chapter investigates electron. It is shown that electron has an intricate internal structure which determines both static and dynamic properties of the electron itself and important parameters of te condensed matter. Stationary “cold” electron (≤0.1eV) is modeled by a thin elastic ring called ector having diameter which is 137,036 times larger Bohr’s radius of hydrogen which consists of specific form of magnetic field. On the basis of the ector model the size, mass, charge, electromagnetic mass, spin and magnetic moment of electron are described. The model of “cold” ring electron in a condensed matter explains from new perspective critical parameters of phase transitions “metal-semiconductor” (Winner’s crystallization) and low temperature and high temperature superconductivity. Ring electron spirals into a void torus as compared to steady moving “hot” electrons (>>0.1эВ). The size of the torus depends on its kinetic energy which makes it possible to describe change...
Atoms, 2019
The anomalous magnetic moment of the electron a e measured in a Penning trap occupies a unique position among high precision measurements of physical constants in the sense that it can be compared directly with the theoretical calculation based on the renormalized quantum electrodynamics (QED) to high orders of perturbation expansion in the fine structure constant α, with an effective parameter α/π. Both numerical and analytic evaluations of a e up to (α/π) 4 are firmly established. The coefficient of (α/π) 5 has been obtained recently by an extensive numerical integration. The contributions of hadronic and weak interactions have also been estimated. The sum of all these terms leads to a e (theory) = 1 159 652 181.606 (11)(12)(229) × 10 −12 , where the first two uncertainties are from the tenth-order QED term and the hadronic term, respectively. The third and largest uncertainty comes from the current best value of the fine-structure constant derived from the cesium recoil measurement: α −1 (Cs) = 137.035 999 046 (27). The discrepancy between a e (theory) and a e ((experiment)) is 2.4σ. Assuming that the standard model is valid so that a e (theory) = a e (experiment) holds, we obtain α −1 (a e) = 137.035 999 1496 (13)(14)(330), which is nearly as accurate as α −1 (Cs). The uncertainties are from the tenth-order QED term, hadronic term, and the best measurement of a e , in this order.
Quantum Wave Mechanics 4th ed., 2022
The fine structure constant alpha (= 0.0072973552... ~ 1/137) is a dimensionless quantity described as a fundamental physical constant characterizing the strength of the electromagnetic interaction. Introduced by Sommerfeld in 1916 to describe the spacing of splitting of spectral lines in multi-electron atoms in terms of electric charge, speed of light and Planck;s constant, the alpha constant represents a relativistic correction to the Bohr theory of the energy level of an electron. The fine structure constant alpha has numerous interpretations including ratio scaling of tangential velocity v to velocity of light c, electromagnetic force to max. force at Compton radius, impedance of free space to electron impedance, Bohr radius to Compton radius, classical electron radius to Compton radius, Compton radius to electromagnetic radius, etc. The inverse fine structure constant 1/alpha (= 137.035999...) is associated with scaling in mass ratios while the reduced fine structure constant alpha/2pi (= 0.0011614...) is associated with scaling in angular velocity and energy ratios. The electron charge to mass ratio e/m in mechanical units has the value 1.758820088E11 rad/sec. This angular velocity is quite small in comparison to the Compton angular frequency of 7.76343E20 rad/sec and is interpreted as a precession frequency. The whirl no q equals the inverse fine structure constant. This slight precession arises as a result of imbalance of electrostatic and magnetostatic energy which creates a torsion defect (loop closure failure) with a precession angle (topological charge) of 0.04458 rad (2,62 deg). This topological charge provides an explanation for origin of electric charge of the electron. This precession also results in wave function interference impeding flow of energy, hence providing an explanation of the origin of electron mass which heretofore has likewise been a mystery. A derivation of the fine structure constant and gyromagnetic spin ratio is presented with calculated values of physical properties of the electron corresponding to observed experimental values.
Academia Biology, 2024
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