Towards identification of a non-abelian state: observation of a quarter of electron charge at $\nu=5/2$ quantum Hall state

Understand

The fractional quantum Hall effect, where plateaus in the Hall resistance at values of coexist with zeros in the longitudinal resistance, results from electron correlations in two dimensions under a strong magnetic field.

• Current flows along the edges carried by charged excitations (quasi particles) whose charge is a fraction of the electron charge.
• While earlier research concentrated on odd denominator fractional values of $\nu$, the observation of the even denominator $\nu=5/2$ state sparked a vast interest.
• This state is conjectured to be characterized by quasiparticles of charge e/4, whose statistics is non-abelian.