Group items tagged atom_interferometry - Advanced Concepts Team

[1012.1194] Does an atom interferometer test the gravitational redshift at the Compton ... - 0 views

fr.arxiv.org/1012.1194

phy atom_interferometry general_relativity

shared by pacome delva on 07 Dec 10 - No Cached

pacome delva on 07 Dec 10

Here is a probably definite answer to the strong polemics around the test of gravitational redshift with atom interferometers, which would be far better than the one done by ACES/PHARAO. Read the abstract it's very ACT like, Luzi should like it :) The original Nature paper is the one of Muller, Peters and Chu (the nobel and secretary of energy in the US): http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html

<div class="cArrow"> </div><div class="cContentInner">Here is a probably definite answer to the strong polemics around the test of gravitational redshift with atom interferometers, which would be far better than the one done by ACES/PHARAO. Read the abstract it's very ACT like, Luzi should like it :) The original Nature paper is the one of Muller, Peters and Chu (the nobel and secretary of energy in the US): <a href="http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html" rel="nofollow" target="_blank">http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html</a></div>

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"Quantum trampoline" measures gravity - 2 views

physicsworld.com/...41208

phy atom_interferometry atom_gravimeter

shared by pacome delva on 15 Dec 09 - Cached

Physicists in France have come up with a new way of using bouncing ultracold atoms to measure the acceleration due to gravity. The technique involves firing vertical laser pulses at a collection of free-falling atoms, which bounces some atoms higher than others. When the atoms recombine at the centre of the experiment, they create an interference pattern that reveals that g is 9.809 m/s2 – just as expected for their Paris lab.
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pacome delva on 15 Dec 09

That's the lab I worked...

<div class="cArrow"> </div><div class="cContentInner">That's the lab I worked...</div>

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Dario Izzo on 16 Dec 09

just being cinical ... but did not we know that g = 9.809 in Paris? I can also create a complex measurement procedure that will held pi = 3.1415, just as expected!!!

<div class="cArrow"> </div><div class="cContentInner">just being cinical ... but did not we know that g = 9.809 in Paris? I can also create a complex measurement procedure that will held pi = 3.1415, just as expected!!!</div>

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pacome delva on 17 Dec 09

well, sure... the interest of such gravimeter is to be absolute, and for now slightly more accurate than the other type of absolute gravimeter which uses retroreflector and interferometry ( http://en.wikipedia.org/wiki/Gravimeter ). While the latter ones reached their limit in term of sensitivity, the atomic ones can be enhanced in many ways (using cooler atoms, better optics, etc...)

<div class="cArrow"> </div><div class="cContentInner">well, sure... the interest of such gravimeter is to be absolute, and for now slightly more accurate than the other type of absolute gravimeter which uses retroreflector and interferometry ( <a href="http://en.wikipedia.org/wiki/Gravimeter" rel="nofollow" target="_blank">http://en.wikipedia.org/wiki/Gravimeter</a> ). While the latter ones reached their limit in term of sensitivity, the atomic ones can be enhanced in many ways (using cooler atoms, better optics, etc...)</div>

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Physics - Atoms in a lattice keep time - 0 views

physics.aps.org/...PhysRevLett.103.063001

phy metrology atomic_clocks atom_interferometry

shared by pacome delva on 05 Aug 09 - Cached

If your wristwatch was as accurate as today’s atomic clocks, it would not gain or lose a second in 80 million years.
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The NIST group traps and cools neutral 171Yb atoms and loads them into a one-dimensional lattice, so that about 30,000 atoms fill several hundred lattice sites.
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Lemke et al. compare their optical lattice clock with the current standard atomic fountain clock and find that the accuracy of the Yb lattice clock potentially challenges the current standard.
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