Superfluidity of "dirty" indirect magnetoexcitons in coupled quantum wells in high magnetic field

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Superfluidity in the quasi-two-dimensional (2D) system of spatially indirect magnetoexcitons in coupled quantum wells (CQW) and unbalanced two-layer electron system in high magnetic field H is considered in the presence of a random field. The problem of the rare gas of magnetoexcitons with dipole-dipole repulsion in a random field has been reduced to the problem of the rare gas of dipole excitons without magnetic field with the effective magnetic mass of a magnetoexciton, which is a function of the magnetic field and parameters of the CQW, in an H-dependent effective random field. The density of the superfluid component nₛ and the temperature Tc of the Kosterlitz-Thouless transition to a superfluid state are obtained as functions of magnetic field H, interlayer separation D and the random field parameters αᵢ and gᵢ. For 2D magnetoexcitonic systems, the rise of the magnetic field H and the interwell distance D is found to increase the effective renormalized random field parameter Q and suppress the superfluid density nₛ and the temperature of the Kosterlitz-Thouless transition Tc. The suppressing influence of D on nₛ and Tc in strong magnetic filed is opposite to the case without magnetic field, when nₛ and Tc increase with the rise of D at fixed total exciton density n. It is shown that in the presence of the disorder at sufficiently large magnetic field H or parameters of the disorder there is no superfluidity at any exciton density.