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Since the discovery of quantum Hall effect, two-dimensional electron system under magnetic field has provided lots of intriguing physics topics both experimentally and theoretically, including integer/fractional quantized Hall conductance, anyon statistics, and non-Abelian particles. Electron-electron interactions play crucial roles in such quantum Hall problems. Even richer phenomena take place for two parallel two-dimensional sheets. Bilayer systems, or more generally multicomponent systems, have additional degrees of freedom, and they allow interlayer paired states at even-denominator filling fraction in each layer, which exhibits the Fermi sea of composite fermions without interactions. I will discuss the interlayer paired state in the presence of the Coulomb interaction and its pairing symmetry, and will make a comment on a possible topological order of the ground state.

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Hiroki Isobe, MIT
Seminar Room of the Institute of Physics II
Contact: Yoichi Ando