Quantum Transmission Coefficient

PineApple2
Messages
49
Reaction score
0
Hello. I have a question, mathematical in nature.
Considering a potential step of height V0 and width a, the amplitude coefficient is
<br /> t=\frac{2k_1k_2e^{-ik_1a}}{2k_1k_2\cos{k_2a}-i(k_1^2+k_2^2)\sin(k_2a)}<br />
Now the transmission coefficient is
<br /> T=|t|^2<br />
So I need to find the absolute value of this expression. I thought about taking the complex conjugate of the denominator and multiply both the numerator and the denominator by this factor (in order to make the denominator real). but this is very messy.
Is there a simpler way to find the absolute value of this expression?
Thanks
 
Physics news on Phys.org
Much simpler. Take the complex conjugate of both the numerator and the denominator separately. If t = N/D, then |t|2 = N*N/D*D
 
Bill_K said:
Much simpler. Take the complex conjugate of both the numerator and the denominator separately. If t = N/D, then |t|2 = N*N/D*D

You are of course correct. Thanks for this obvious answer :-)
 
Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
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
Is it possible, and fruitful, to use certain conceptual and technical tools from effective field theory (coarse-graining/integrating-out, power-counting, matching, RG) to think about the relationship between the fundamental (quantum) and the emergent (classical), both to account for the quasi-autonomy of the classical level and to quantify residual quantum corrections? By “emergent,” I mean the following: after integrating out fast/irrelevant quantum degrees of freedom (high-energy modes...

Similar threads

Back
Top