Davis–Putnam algorithm - Revision history

en>Monkbot: /* References */Task 3: Fix CS1 deprecated coauthor parameter errors

2014-05-07T15:33:47Z

References: Task 3: Fix CS1 deprecated coauthor parameter errors

← Older revision		Revision as of 17:33, 7 May 2014
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	~~[[Image:Molasses.gif\|350px\|thumb\|Optical Molasses Schematic]]~~		Emilia Shryock is my name but you can call me anything you like. He is really fond of doing ceramics but he is having difficulties to find time for it. Since she was eighteen she's been operating as a receptionist but her marketing never arrives. California is our beginning location.<br><br>Also visit my website; over the counter std test - [http://www.articlecube.com/profile/Nydia-Lyons/532548 Web Site] -

	~~'''Optical molasses'''~~ is ~~a [[laser cooling]] technique that~~ can ~~cool down neutral [[atom]]s to temperatures colder than a [[magneto-optical trap]] (MOT)~~. ~~An optical molasses consists~~ of ~~3 pairs of counter-propagating circularly polarized laser beams intersecting in the region where the atoms are present. The main difference between optical molasses and a MOT~~ is ~~the absence of magnetic field in the former. While a typical Sodium MOT can cool atoms down~~ to ~~300μK, optical molasses can cool the atoms down to 40μK, an order of magnitude colder~~.

	~~==History==~~

	~~When laser cooling~~ was ~~proposed in 1975,~~ a ~~theoretical limit on the lowest possible temperature was predicted~~. Known as the '''Doppler Limit''', <math> T_d= \hbar \Gamma / {2 k_b} </math>, this was given by the lowest possible temperature attainable considering the cooling of two-level atoms by Doppler cooling and the heating of atoms due to momentum diffusion from the scattering of laser photons. ~~Here,~~ <~~math~~> ~~\Gamma~~ <~~/math~~>~~, is~~ the ~~natural line~~-~~width of the atomic transition, <math> \hbar <~~/~~math>, is Planck's constant and, <math> k_b <~~/~~math>, is Boltzmann's constant~~.

	~~Experiments at the [[National Institute of Standards and Technology]], Gaithersburg, found the temperature of cooled atoms to be well below the theoretical limit~~. ~~Initially, it was a surprise to theorists, until the full explanation came out.~~

	~~==Theory==~~

	The best explanation of the phenomenon of optical molasses is based on the principle of polarization gradient cooling. Counterpropagating beams of circularly polarized light cause a standing wave, where the [[light polarization]] depends on the spatial location. The AC [[Stark Effect\|Stark Shift]] of atoms in different [[Fine structure\|magnetic sub-levels]] is also spatially dependent. The basic idea is that atoms moving with a velocity climb a polarization gradient hill, thereby losing their velocity. At the top of the hill, atoms are resonant with the other molasses beams, absorb a photon and decay into a lower energy magnetic sub-level, thereby having shed some of their velocity. {{Citation needed\|reason=I believe that this is Sisyphus cooling. Optical Molasses is an extension of Doppler cooling\|date=April 2011}}

	~~==References==~~
	*''Cooling of gases by laser radiation'', T.W. Hänsch, and A.L. Schawlow, Optics Communications, 13, 68 (1975).

	*''Laser cooling below the Doppler limit by polarization gradients: simple theoretical models'', [[Jean Dalibard]] ~~and Claude [[Claude Cohen~~-~~Tannoudji\|Cohen-Tannoudji]] JOSA B, Vol. 6, Issue 11, pp. 2023- (1989)~~

	~~[[Category:Atomic, molecular, and optical physics]]~~

en>Ugog Nizdast: Reverted 1 edit by Dorybadboy identified as test/vandalism using STiki

2014-01-27T10:21:16Z

Reverted 1 edit by Dorybadboy identified as test/vandalism using STiki

← Older revision		Revision as of 12:21, 27 January 2014
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	~~She~~ is ~~recognized by~~ the ~~name~~ of ~~Myrtle Shryock~~. ~~He used~~ to ~~be unemployed but now he is~~ a ~~pc operator but his promotion~~ by ~~no means comes. To collect badges is what her family members~~ and ~~her appreciate. California is exactly where her home is but she needs~~ to ~~transfer simply because~~ of ~~her family members~~.<br><br>~~Check out my web blog [http:~~//~~www~~.~~articlestunner~~.~~com/cures~~-~~for~~-the-~~yeast~~-~~infection~~-~~suggestions-to-use-now/ at home std testing~~]		[[Image:Molasses.gif\|350px\|thumb\|Optical Molasses Schematic]]

			'''Optical molasses''' is a [[laser cooling]] technique that can cool down neutral [[atom]]s to temperatures colder than a [[magneto-optical trap]] (MOT). An optical molasses consists of 3 pairs of counter-propagating circularly polarized laser beams intersecting in the region where the atoms are present. The main difference between optical molasses and a MOT is the absence of magnetic field in the former. While a typical Sodium MOT can cool atoms down to 300μK, optical molasses can cool the atoms down to 40μK, an order of magnitude colder.

			==History==

			When laser cooling was proposed in 1975, a theoretical limit on the lowest possible temperature was predicted. Known as the '''Doppler Limit''', <math> T_d= \hbar \Gamma / {2 k_b} </math>, this was given by the lowest possible temperature attainable considering the cooling of two-level atoms by Doppler cooling and the heating of atoms due to momentum diffusion from the scattering of laser photons. Here, <math> \Gamma </math>, is the natural line-width of the atomic transition, <math> \hbar </math>, is Planck's constant and, <math> k_b </math>, is Boltzmann's constant.

			Experiments at the [[National Institute of Standards and Technology]], Gaithersburg, found the temperature of cooled atoms to be well below the theoretical limit. Initially, it was a surprise to theorists, until the full explanation came out.

			==Theory==

			The best explanation of the phenomenon of optical molasses is based on the principle of polarization gradient cooling. Counterpropagating beams of circularly polarized light cause a standing wave, where the [[light polarization]] depends on the spatial location. The AC [[Stark Effect\|Stark Shift]] of atoms in different [[Fine structure\|magnetic sub-levels]] is also spatially dependent. The basic idea is that atoms moving with a velocity climb a polarization gradient hill, thereby losing their velocity. At the top of the hill, atoms are resonant with the other molasses beams, absorb a photon and decay into a lower energy magnetic sub-level, thereby having shed some of their velocity. {{Citation needed\|reason=I believe that this is Sisyphus cooling. Optical Molasses is an extension of Doppler cooling\|date=April 2011}}

			==References==
			*''Cooling of gases by laser radiation'', T.W. Hänsch, and A.L. Schawlow, Optics Communications, 13, 68 (1975).

			*''Laser cooling below the Doppler limit by polarization gradients: simple theoretical models'', [[Jean Dalibard]] and Claude [[Claude Cohen-Tannoudji\|Cohen-Tannoudji]] JOSA B, Vol. 6, Issue 11, pp. 2023- (1989)

			[[Category:Atomic, molecular, and optical physics]]

en>Helpful Pixie Bot: ISBNs (Build KC)

2012-05-06T19:10:57Z

ISBNs (Build KC)

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She is recognized by the name of Myrtle Shryock. He used to be unemployed but now he is a pc operator but his promotion by no means comes. To collect badges is what her family members and her appreciate. California is exactly where her home is but she needs to transfer simply because of her family members.<br><br>Check out my web blog [http://www.articlestunner.com/cures-for-the-yeast-infection-suggestions-to-use-now/ at home std testing]