Activation study of collective excitations of the soliton-lattice phase in theν=1double-layer quantum Hall state

Abstract

We investigate thermal excitations of the pseudospin soliton lattice in the double-layer quantum Hall ͑QH͒ state at total Landau-level filling factor = 1 by detailed measurements of the activation energy gap, where the pseudospin represents the layer degree of freedom. In a tilted magnetic field, the activation energy gap of the double-layer = 1 QH state shows a minimum near the phase transition point between the commensurate and incommensurate states. From a comparison of the in-plane field dependence of the activation energy gap with theories, we suggest that the minimum in the activation energy gap is due to collective modes of the soliton lattice.

Large Zeeman Splitting in Out-of-Plane Magnetic Field in a Double-Layer Quantum Point Contact

“…A well-known phenomenon in single-layer systems, such as quantum Hall effect (QHE), reveals further richness in double-layer systems . [1][2][3][4][5][6][7] For example, a prediction of Kosterlitz-Thouless transition in association with the dissociation of pseudospin vortices ("meron"s) is discussed . [8][9][10][11] Interestingly, these topologically protected pseudospin quasiparticles are considered to be non-Abelian.…”