Ithaca College

Where is the coldest place at IC?

You might guess that it is the campus quad on a blustery winter day that gets inside your coat and down to your bones, or in the ice cream freezer at the dining hall, or maybe the liquid nitrogen in the chemistry lab.

But no! – it is a cloud of rubidium atoms in the optics lab in the physics department!
 

The small bright dot in the center of the picture is a cloud of about 10 million rubidium atoms which are at a temperature of -273.15 °C (−459.67 °F). That’s absolute zero! In fact, the atoms are at a temperature of less than 1/1000th of a degree above absolute zero. Their kinetic motion is slowed down by laser beams coming from all directions. The atoms are compressed into a ball by the same laser beams together with an electromagnet.  The system is called a Magneto-Optical Trap (MOT).

The MOT is the result of more than 2 years of work by Associate Professor Bruce Thompson with recent alum Judith Olson’11 and students Ryan Jefferis’12, Josh Cheng’13, and Drake Builta’14. Alum Evan Salim’03 (PhD 2011) inspired this research direction and provide technical help.  The MOT system will be used for further faculty and student research projects and in the physics advanced teaching laboratory.