Orthoexciton-to-paraexciton conversion rate in Cu${}_2$O at sub-Kelvin temperatures

Yusuke Morita, Yukihiro Akiyama, Yuki Haita +2

We measured the conversion rate from 1s orthoexcitons to 1s paraexcitons in Cu${}_2$O below 1 K using a dilution refrigerator. To determine the conversion rate, we performed time-res…