All Questions
Tagged with coherent-states time-evolution
8
questions
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242
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It seems that expectation value of $H$ on coherent states is independent of time? But why?
Let's say the particle is in the state $| \psi(0) \rangle = \exp(-i\alpha p/\hbar) |0 \rangle$, where $p$ is the momentum operator.
I have to show that $| \psi(0) \rangle$ is a coherent state and to ...
- 81
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0
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Evolution of Quantum Harmonic Oscillator into coherent state
Why does a quantum harmonic oscillator that is driven by an electromagnetic wave in cosine form with its frequency equal to the resonance frequency of the oscillator evolve from its groundstate into a ...
- 95
2
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2
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Driven Quantum Harmonic Oscillator
Consider the Hamiltonian
$$
H = \frac{p^2}{2} + \frac{ x^2}{2} - F(t) x.
$$
This is essentially a time dependent shifted harmonic oscillator, which can be represented as
$$
H' = \frac{p^2}{2} + \frac{...
- 427
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What is the meaning of the time evolution of a product of coherent states of the QHO?
I am trying to analyze the dynamics of a coupled quantum harmonic oscillator (cQHO) system. The Hamiltonian of the system is given by:
\begin{equation}
\hat{H}_{Coupled}=\frac{1}{2m}\sum_{j}\hat{p}_{j}...
- 325
3
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1
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What does "coherent evolution" of an $N$-body quantum system mean?
In classical physics we know of coherence of waves and in quantum physics we identify coherent states.
While those are clearly defined concepts/terms, in literature we regularly encouter also that a $...
- 33
3
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2
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476
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Why don't the oscillator coherent states disperse in time?
A Gaussian wavepacket is made of a continuum of frequencies (or energies) and stretches in time due to the phenomenon of dispersion: the different plane wave components with different frequencies ...
- 26.8k
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Time evolution of operators with explicit time dependence in case of time dependent Hamiltonian
In case of a time dependent Hamiltonian of the sort $$H=\frac{p^2}{2m}+\frac{1}{2}m \omega(t) x^2$$ I have solved for the time evolution operator using the Schrodinger equation and got $U(t,0)$. If, I ...
- 1,212
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Time evolution of squeezed states
I cannot find anywhere on the web or on some books the esplicit expression for the time evolution of squeezed states (defined as $|\xi\rangle = S(\xi)|0\rangle = e^{\frac{1}{2}(\xi^*a^2-\xi (a^\dagger)...
- 479