Novel excitonic states in quantum Hall systems: Bound states of spin waves and a valence band hole

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If the Zeeman energy is small, the lowest energy excitations of a two dimensional electron gas at filling factor nu=1 are spin waves (spin flip excitations). At nu slightly larger (smaller) than unity, reversed spin electrons (spin holes) can form bound states with K spin waves that are known as skyrmions, Sₖ- (antiskyrmions, Sₖ+). It is suggested in this work that a valence hole can also bind K spin waves to form an excitonic complex Xₖ+, analogous to the Sₖ+. One spin hole of the Sₖ+ is simply replaced by the valence hole. At nu<=1, a small number of Sₖ+'s are present before introduction of the valence hole. The (Sₖ+)-(Xₖ+) repulsion leads to correlations and photoluminescence similar to those of a dilute electron-(charged-exciton) (e-X-) system at nu<=1/3. At nu>=1, the (Sₖ-)-(Xₖ+) attraction can potentially lead to different behavior.