Questions tagged [cold-atoms]
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Inconsistency in scattering length of spherical well potential
I'm trying to understand the scattering length of the spherical well potential
$$V(r)=\begin{cases}-V_0&r<r_0\\ 0&r>r_0\end{cases}$$
The $V_0>0$ (attractive) case is fairly well ...
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Flux pinning upon a ultracold vapor of neutral atoms
Suppose I have a mixture of two different atoms A and B, both with an even but different number of electrons which fully fill both of their outermost shells. The two are different elements.
Now, ...
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Ultracold magnetic traps for uranium enrichment
As noted by Mr. Gremlin in this post: How is it possible to accelerate a neutron?
Crudely paraphrasing, subatomic particles with non-zero magnetic dipole moments interact with magnetic fields to give ...
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Gas or liquid? a Bose-Einstein condensate
It is often said that a Bose-Einstein condensate of cold atoms is a gas. But because of Andrews' discovery of the critical temperature, we know that a gas and a liquid is not fundamentally different. ...
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Why are Alkali atoms used in many Cold Atom experiments?
It seems that alkali atoms are often used in cold atom experiments. The first BEC was formed with alkali atoms, and many modern experiments used Alkalis. What is special about having a single electron ...
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$s$-wave scattering approximation of the two-body interaction
In quantum gases, one usually approximates the two-body interaction $V(\boldsymbol{r})$ with a s-wave delta potential $$V_{\text{pseudo}}(\boldsymbol{r}) = \frac{4\pi \hbar^2 a}{m} \delta (\boldsymbol{...
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Creating entangled states via Rydberg blockade
I was watching a talk by Prof. Mikhail Lukin and I have a silly question.
In the talk, he discussed that a typical procedure for generating a Bell pair consists of using the Rydberg blockade on two ...
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Molecular orbital notation
I'm reading about papers about atom-ion interaction. There are some states as showned above.
The notations of the states look like molecular orbital since $\Sigma$ and $\Pi$ is usually used in orbital ...
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Cold atoms in optical tweezers
Can someone recommend a good reference for learning about cold atoms in/with optical tweezers? I am interested in both the theoretical and experimental aspects. On my own, I couldn't find any ...
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Why is a singlet state potential greater than triplet state potential in the Feshbach resonance experiment?
I googled the Feshbach resonance in the Wikipedia and I have some problems. In German Wikipedia, they consider Li-6 molecule as an example.
For these two different spin configurations(singlet and ...
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Atom Interferometer Contrast
I have made a simulation of a Raman beam based atom interferometer in a Mach-Zehnder configuration. In this way, the electronic state of the atom changes as well as the momentum when diffraction by ...
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How a does a RF magnetic field interact with trapped atoms in evaporative cooling?
In the paper “Evaporative Cooling of Trapped Atoms,” [Advances in Atomic Molecular And Optical Physics 37, 181–236 (1986)] by Wolfgang Ketterle and N. J. Van Druten, they claimed the matrix element ...
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How does a RF-induced evaporative cooling remove hotter atoms in the dressed state picture?
I am stuck in the problem of evaporative cooling in a magnetic trap.
$\textbf{Introduction}$
In the magnetic trap, I assumed the trap is an Ioffe-Pritchard trap. So the Majorona loss is prohibited. ...
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Why is the Lamor frequency much faster than trapping frequency required in the magnetic trap?
I study the magnetic trapping recently. I met a problem. I consider the original quadruple magnetic trap. In the original quadruple magnetic trap, the magnetic vanishes at the center. The Majorana ...
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Why doesn't optical pumping work when there is no external field to cause Zeeman splitting
I discovered a strange phenomenon in an experiment related to optic pumping and magnetic resonance.
In this experiment, I optically pump electrons in Rb85 to the $5S_{1/2}, F=2, m_{F}=+2$ state and in ...
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