MAG­NETIC TRAP CAP­TURES ATOMS

Science Illustrated - - TECHNOLOGY/ABSOLUTE ZERO -

FIRST, LASERS COOL ATOMS

1 Laser beams com­ing from six di­rec­tions slow down a cloud of mil­lions of atoms. A mag­netic trap cap­tures the atoms, cool­ing them to 100 mil­lionths of a de­gree above ab­so­lute zero.

ATOM CLOUD TRANSFERRED TO CHIP

2 Af­ter the in­tro­duc­tory cool­ing in the vac­uum cham­ber, the atom cloud moves to the cen­tre of an atom chip. The mag­ne­tized atom chip main­tains the atom cloud in a mag­netic field.

RA­DIO WAVES RE­MOVE WARM ATOMS.

3 Ra­dio waves de­flect hot atoms out of the cloud, just like hot tea is cooled, when you blow on it. The cloud becomes so cold that the atoms pro­duce a Bose-Einstein con­den­sate at a few bil­lionths of a de­gree above zero.

EX­PAN­SION COOLS ATOM CLOUD ONCE AGAIN

4 The trap weak­ens, and weight­less­ness en­sures a life time of 10-20 sec­onds, so the cloud ex­pands, and the atoms are cooled even more, to a record of 50 bil­lionths of a de­gree above zero.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.