Bolometric shot noise detection in coupled quantum contacts

Joel Stettenheim, Feng Pan, Zhongqing Ji +6 more

Juan Carlos Cuevas, A. Martín‐Rodero, A. Levy Yeyati

Joel Stettenheim, Madhu Thalakulam, Feng Pan +4 more

Masayuki Hashisaka, Yoshiaki Yamauchi, Shuji Nakamura +5 more

We demonstrate the on‐chip bolometric detection of the quantum shot noise emitted from a biased quantum point contact (source QPC) by using another QPC (detector QPC). These QPCs are capacitively coupled to each other to exchange high‐frequency (∼GHz) fluctuation. By applying the noise thermometry to both QPCs at several temperatures, we prove that the excess noise temperature of detector QPC is perfectly proportional to that of source QPC.

D. C. Glattli

Masayuki Hashisaka, Yoshiaki Yamauchi, Shuji Nakamura +3 more

We demonstrate a scheme to detect the quantum shot noise in coupled mesoscopic systems. By applying the noise thermometry to the capacitively coupled quantum point contacts (QPCs) we prove that the noise temperature of one QPC is in perfect proportion to that of the other QPC which is driven to nonequilibrium to generate quantum shot noise. The present mesoscopic bolometry, which is sensitive to the energy flow of $\ensuremath{\sim}1\text{ }\text{fW}$, allows us to detect the energy exchange between quantum systems at finite frequency and can also be applied for diverse precise measurements.