What Happens When the Electron Energy E Equals Potential V in Quantum Mechanics?

joe2005
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I am taking a course in solid state electronics at the university and I was thinking about one detail in the calculation of k. In a simple situation like a step potential we say that k=sqrt(2m*abs(E-V))/hbar . Now my question is What happens if the electron approaching the barrier is having an energy E=V. According to the formula k will be zero. Does that me that the electron will not "move" in the barrier. Is (E=V) a resemblence of the infinite potential case but at a single E value?

Thanks...
 
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If you are taking a course in solid state physics you should have covered this in a previous course. " Is (E=V) a resemblence of the infinite potential case but at a single E value?" I haved no idea what you mean by that but: FINITE is not the same as INFINITE! Unless your step is to an "infinite" potential, you have a finite potential and there is a probability that the electron will penetrate the potential step. If I remember correctly the standard method of solving the differential equation, to determine what that probability is, is the "WKB" approximation.
 
Sorry if I wasn't clear. What I meant is that if at E=V our k=0 and the electron has a zero chance of penetration then this means that at this specific case the "FINITE" barrier will acts as an "INFINITE" one from the point of view of that electron having E=V...
 
There are no stationary states, if that's your question. There are only scattering states, like with a free particle.
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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