Intrinsic Gap and Exciton Condensation in the νT=1 Bilayer System

PAULA GIUDICI; KOJI MURAKI; NORIO KUMADA; T. FUJISAWA

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Año: 2010 vol. 104 p. 56802 - 56805

0031-9007

We investigate the quasiparticle excitation of the bilayer quantum Hall (QH) system at a total filling factor νT=1 in the limit of negligible interlayer tunneling under a tilted magnetic field. We show that the intrinsic quasiparticle excitation is of purely pseudospin origin and solely governed by the inter- and intralayer electron interactions. A model based on exciton formation successfully explains the quantitative behavior of the quasiparticle excitation gap, demonstrating the existence of a link between the excitonic QH state and the composite fermion liquid. Our results provide a new insight into the nature of the phase transition between the two states.