Paired Composite Fermion Phase Of Quantum Hall Bilayers At V = 1/2 + 1/2

摘要

We provide numerical evidence for composite fermion pairing in quantum Hall bilayer systems at filling v = 1/2 + 1/2 for intermediate spacing between the layers. We identify the phase as p_x + ip_y pairing, and construct high accuracy trial wave functions to describe the ground state on the sphere. For large distances between the layers, and for finite systems, a competing "Hund's rule" state, or composite fermion liquid, prevails for certain system sizes.