I will talk about two experiments with which we use our (bosonic) 41K
- 87Rb system to probe properties of nature.
First experiment is on the universality of three-body physics for
hetero-nuclear mixtures. The measured three-body loss coefficients
around Feshbach resonances matched quite well with the coefficient
obtained from 40K - 87Rb system by JILA group, indicating universal
behavior of three-body physics.
Second experiment is to measure the variation of fundamental constants
using ultracold molecules. By measuring the frequency of a microwave
transition between loosely bound ultracold molecules, we determined
the upper-limit of variation of electron-to-proton mass ratio.