Evidence for Skyrmions and Single Spin Flips in the Integer Quantized Hall Effect.

We have employed tilted-field magneto-transport measurements of the energy gap for the odd-integer quantized Hall states at Landau level filling factors ν = 1,3 and 5 to determine the spin of thermally excited quasielectron-quasihole pairs. At ν = 1 our data show that as many as 7 electron spin flips accompany such excitations, while at ν = 3 and 5 apparently only a single spin flips. These results lend support to the recent suggestions that " Skyrmionic " quasiparticles are the lowest-lying charged excitations of the fully-polarized ν = 1 quantum Hall fluid but are not at the higher odd-integer fillings.