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In nuclear physics, beta decay is a type of radioactive decay in which a beta ray (fast energetic electron or positron) and a neutrino are emitted from an atomic nucleus. Electron capture is sometimes called inverse beta decay , though this term usually refers to the interaction of an electron antineutrino with a proton.
In atomic physics and chemistry, an atomic electron transition (also called an atomic transition, quantum jump, or quantum leap) is an electron changing from one energy level to another within an atom [1] or artificial atom. [2] The time scale of a quantum jump has not been measured experimentally.
Within a semiconductor crystal lattice, thermal excitation is a process where lattice vibrations provide enough energy to transfer electrons to a higher energy band such as a more energetic sublevel or energy level. [3] When an excited electron falls back to a state of lower energy, it undergoes electron relaxation (deexcitation [4]).
In solid-state physics of semiconductors, carrier generation and carrier recombination are processes by which mobile charge carriers (electrons and electron holes) are created and eliminated. Carrier generation and recombination processes are fundamental to the operation of many optoelectronic semiconductor devices , such as photodiodes , light ...
The one-electron universe postulate, proposed by theoretical physicist John Wheeler in a telephone call to Richard Feynman in the spring of 1940, is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time.
If the experiment is conducted using charged particles like electrons, there will be a Lorentz force that tends to bend the trajectory in a circle. This force can be cancelled by an electric field of appropriate magnitude oriented transverse to the charged particle's path. Spin values for fermions. Electrons are spin-1/2 particles.
The two charge carriers, electrons and holes, will typically have different drift velocities for the same electric field. Quasi-ballistic transport is possible in solids if the electrons are accelerated across a very small distance (as small as the mean free path), or for a very short time (as short as the mean free time). In these cases, drift ...
[218] [219] Heating the cathode energizes the electrons in it, aiding electron emission, [220] while at the same time current is supplied to the cathode; typically anywhere from 140 mA at 1.5 V to 600 mA at 6.3 V. [221] The cathode creates an electron cloud (emits electrons) whose electrons are extracted, accelerated and focused into an ...