论文标题
在非共振抽水下凝聚的激子 - 果龙冷凝物的阻力
Drag force of a exciton-polariton condensate under non-resonant pumping
论文作者
论文摘要
半导体微腔中的激子 - 果龙冷凝物构成了一种新型的非平衡性超氟。在最近的实验中[P. Stepanov，{\ it等。 al。，} nat。社区。 {\ bf 10}，1038（2019）]，已经研究了谐振泵送下极性浓缩物中集体激发的分散性关系，重点是对较长寿命的激子储层在确定超富度的作用中的作用。受到这种实验进步的启发，我们通过计算在北极凝管中移动的经典杂质上施加的阻力，研究了在非谐波泵送下凝结激子孔子凝结物的超流量。对于在间隙相中制备的非共振泵浦极性冷凝物，由于储层的模式，当杂质的速度较小时，阻力可能很大。此外，随着速度的增加，阻力可以减小。对于不是很大的速度，如果将冷凝物调谐为耗散，则阻力会增强。当冷凝物接近间隙相和无间隙相之间的过渡点时，阻力与平衡超氟相似。我们目前的工作揭示了储层模式对偏光基冷凝物与非共鸣泵的超流量性能的影响。
Exciton-polariton condensate in semiconductor microcavities constitute a novel kind of non-equilibrium superfluid. In a recent experiment [P. Stepanov, {\it et. al.,} Nat. Commun. {\bf 10}, 1038 (2019)], the dispersion relation of collective excitations in a polariton condensate under the resonant pumping has been investigated with the emphasis on the role of reservoir of long-lived excitons in determining the superfluidity. Inspired by such an experimental advance, we study the superfluidity of a exciton-polaritonn condensate under non-resonant pumping by calculating the drag force exerted on a classical impurity moving in a polariton condensate. For a non-resonant pumped polariton condensate prepared in the gapped phase, due to the reservoir's modes, the drag force can be large when the velocity of the impurity is small. Besides, as the velocity increases, the drag force can decrease. For not very large velocity, the drag force is enhanced if the condensate is tuned to be more dissipative. When the condensate is close to the transition point between the gapped phase and the gapless one, the drag force is similar to that of the equilibrium superfluid. Our present work reveals the effects of the reservoir's modes on the superfluidity properties of a polariton condensate with the non-resonant pumping.
