  We report experiments on a Laughlin quasiparticle interferometer where the
entire system is on the 1/3 primary fractional quantum Hall plateau.
Electron-beam lithography is used to define an approximately circular 2D
electron island separated from the 2D bulk by two wide constrictions. The
interferometer consists of counterpropagating chiral edge channels coupled by
quantum-coherent tunneling in the two constrictions, thus enclosing an island
area. Interference fringes are observed as conductance oscillations, similar to
the Aharonov-Bohm effect. The flux and charge periods of the interferometer
device are calibrated with electrons in the integer quantum Hall regime. In the
fractional regime we observe magnetic flux and charge periods h/e and e/3,
respectively, corresponding to creation of one quasielectron in the island.
Quantum theory predicts a 3h/e flux period for charge e/3, integer statistics
particles. Accordingly, the observed periods demonstrate the anyonic statistics
of Laughlin quasiparticles.
