into different QWs. The spatial charge separation enhances the IX radiative lifetime by orders of magnitude (up to a $\mu$s-range) as compared to DXs, while still maintaining the Coulomb correlation between the electrons and holes.

Different studies have addressed the manipulation of IXs on time scales shorter than their lifetime. The trapping of IXs even down to the single particle level [@Schinner_PRL110_127403_13] was demonstrated using a variety of potential landscapes created by optical [@Ref9], magnetic [@Ref10], electric [@Ref11; @Ref12] or strain [@Ref13] fields. Applied electric fields, in particular, can control the IX energy and lifetime via the quantum confined Stark effect (QCSE) induced by ${F_\mathrm{Z}}$ [@Ref14]. Proposals for all-optical control via remote dipolar interactions of IX fluids have also been put forward [@Ref3]. Recently, reference [@Ref15] has introduced an exciton optoelectronic transistor, where the exciton flow (over a few $\mu$m) induced by potential energy gradients has been exploited for the realization of simple operations on photonic signals, such as directional switching and merging [@Ref16; @Ref17]. Several groups have also demonstrated the transport of IXs over longer distances by diffusion [@Ref18], drift [@Ref19] as well as by moving electrostatic lattices [@Ref20]. Finally, we have recently shown that IX can be efficiently 