Evolution of Quasiparticle Charge in the Fractional Quantum Hall Regime

The charge of quasiparticles in a fractional quantum Hall (FQH) liquid, tunneling through a partly reflecting constriction with transmission $t$, was determined via shot noise measurements. In the $\nu =1\mathrm{}/3$ FQH state, a charge smoothly evolving from $e^{*}=e/3$ for $t_{1/3}\cong 1$ to $e^{*}=e$ for $t_{1/3}\ll 1$ was determined, agreeing with chiral Luttinger liquid theory. In the $\nu =2\mathrm{}/5$ FQH state the quasiparticle charge evolves smoothly from $e^{*}=e/5$ at $t_{2/5}\cong 1$ to a maximum charge less than $e^{*}=e/3$ at $t_{2/5}\ll 1$. Thus it appears that quasiparticles with an approximate charge $e/5$ pass a barrier they see as almost opaque.