Orbital spins of the collective excitations in Hall liquids

We show that the Chern-Simons-Ginzburg-Landau theory of the quantum Hall effect needs a modification, because the order parameter in that theory carries an intrinsic orbital angular momentum. This quantum number contains additional information about the topological order of the Hall liquids. We propose to measure this angular momentum by circular-polarized Raman scattering. © 1994 The American Physical Society.