Shot-noise evidence of elementary charge fission into fractional charges in a quantum Hall regime

We have experimentally evidenced an elementary charge fission, in which an elementary charge in an integer quantum Hall (IQH) system breaks up into fractional charges at a local fractional quantum Hall (FQH) state. Shot-noise measurements establish the e/3-charge of tunneling quasiparticles through the local FQH state, which is prepared in a low-density region near a quantum point contact (QPC) in an IQH system. The shot noise is proportional to T1(1 − T1) over a wide range of T1 (1/3 < T1 < 0.9), where T1 is the transmission probability of the IQH edge channel. This binomial distribution factor indicates that fractional quasiparticles emerge from the IQH system, and thus the tunneling process can be referred to as the elementary charge fission. The study of this fission process will enable us to elucidate the dynamics of Laughlin quasiparticle creation in FQH systems.