A NOVEL MERON-INDUCED PSEUDOSPIN WAVE IN THE BILAYER QUANTUM HALL COHERENT STATE AND THE RESIDUAL ZERO-BIAS PEAK IN TUNNELING CONDUCTANCE

Abstract

In the bilayer quantum Hall coherent state for νT deviating slightly from unity, we show that, instead of the global order parameter, the periodic domain structure accompanying the charged meron pairs spontaneously breaks the pseudospin U(1) rotational symmetry. The motion of meron pairs induces a novel pseudospin wave. The long-range order of the periodic domains in a low bias voltage range leads to the residual zero-bias peak in the tunneling conductance, which can be distinct from the pseudopsin Goldstone feature in a high bias voltage range.