翻訳と辞書 |
Zeeman slower : ウィキペディア英語版 | Zeeman slower
A Zeeman slower is a scientific apparatus that is commonly used in quantum optics to cool a beam of atoms from room temperature or above to a few kelvins. At the entrance of the Zeeman slower the average speed of atoms is on the order of a few hundred m/s. The spread of velocity is also in the order of a few hundred m/s. Final speed at the exit of the slower is few 10 m/s with an even smaller spread. A Zeeman slower consists of a cylinder, through which the beam travels, a pump laser that is shone on the beam in the direction opposite to the beam's motion, and a magnetic field (commonly produced by a solenoid-like coil) that points along the symmetry axis of the cylinder and varies spatially along the axis of the cylinder. The pump laser, which is required to be near-resonant to an atomic or molecular transition, Doppler slows a certain velocity class within the velocity distribution of the beam. The spatially varying Zeeman shift of the resonant frequency enables lower and lower velocity classes to be resonant with the laser, as the atomic or molecular beam propagates along the slower, hence slowing the beam. ==History==
It was first developed by William D. Phillips (who was awarded the Nobel Prize in Physics for this discovery in 1997 together with Steven Chu and Claude Cohen-Tannoudji ''"for development of methods to cool and trap atoms with laser light"''〔(Nobel prize in physics press release, 1997 )〕) and Harold J. Metcalf.〔W. D. Phillips and H. Metcalf, Phys. Rev. Lett. 48, 596 (1982)〕 The achievement of these low temperatures lead the way for the experimental realisation of Bose–Einstein condensation, and a Zeeman slower can be part of such an apparatus.
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Zeeman slower」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|