Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev Lett. 2010 Apr 23;104(16):166802. doi: 10.1103/PhysRevLett.104.166802. Epub 2010 Apr 21.
The effect of impurities which induce local interlayer tunneling in bilayer exciton condensates is discussed. We show that a localized single-fermion bound state emerges inside the gap for any strength of impurity scattering and calculate the dependence of the impurity state energy and wave function on the potential strength. We show that such an impurity-induced single-fermion state enhances the interlayer coherence around it, and is similar to the superconducting proximity effect. As a direct consequence of these single-impurity states, we predict that a finite concentration of such impurities will increase the critical temperature for exciton condensation.
本文讨论了杂质对双层激子凝聚体中局域层间隧道的影响。结果表明，在任意强度的杂质散射下，在能隙内会出现局域的单粒子束缚态，并计算了杂质态能量和波函数对势强度的依赖关系。结果表明，这种杂质诱导的单粒子态增强了其周围的层间相干性，类似于超导近邻效应。作为这些单杂质态的直接结果，我们预测，一定浓度的此类杂质将提高激子凝聚的临界温度。
