Optical absorption in the soliton lattice state of a double quantum well system

Abstract

When the separation between layers in a double-quantumwell system is sufficiently small, the ground state of the twodimensional electron gas at filling factor ν = 1 has an interwell phase coherence even in the absence of tunneling. For non-zero tunneling, this coherent state goes through a commensurate-incommensurate transition as the sample is tilted with respect to the quantizing magnetic field at ν = 1. In this article, we compute the optical (infrared) absorption spectrum of the coherent state from the commensurate state at small tilt angle to the soliton-lattice state at larger tilt angle and comment on the possibility of observing experimentally the distinctive signature of the soliton lattice.

Observation of Collapse of Pseudospin Order in Bilayer Quantum Hall Ferromagnets

“…The results are surprising by revealing large correlation effects in a range of ∆SAS Ec and d lB values where magnetotransport results find well-defined QH signatures. Further studies, including absorption across the fundamental gap between valence and conduction bands [30,31], should clarify if the correlated state with reduction of pseudospin order displays the properties of an electronhole excitonic quantum fluid.…”