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3 votes
1 answer
104 views

Adiabatic Approximation in the spin 1/2 System

I am studying the following Hamiltonian: $$H(t) = \begin{bmatrix} \frac{t\alpha}{2} & H_{12} \\ H_{12}^* & -\frac{t\alpha}{2} \\ \end{bmatrix}$$ I want to assume that $\...
A. Radek Martinez's user avatar
0 votes
1 answer
165 views

Finite-time effects in Landau Zener

Consider a two level system with a Landau-Zener Hamiltonian of the form $$\hat{H}=\begin{pmatrix}v t&\beta\\\beta&-v t\end{pmatrix}.$$ The Landau-Zener formula provides a closed form for the ...
TopoLynch's user avatar
  • 503
4 votes
0 answers
265 views

Implement Adiabatic Elimination on Hamiltonians?

Adiabatic elimination is the process of truncating a Hamiltonian's Hilbert space to the "slow" states you care about. You throw out the "fast" eigenstates to produce a smaller ...
KF Gauss's user avatar
  • 7,931
1 vote
0 answers
126 views

What is the difference between arriving at the 'avoided crossing' point of a two-level system adiabatically and non-adiabatically?

In the simplest case of the 'avoided crossing phenomenon' we can assume a two level system that its eigenstates $E_1(n)$ and $E_2(n)$ are functions of some continuous variable n, and there is some ...
Qexp's user avatar
  • 11