OFF state. (c),(d) Control of IX flux by the gate electrode of EXAT$_6$. All SAW beams are generated by applying ${P_\mathrm{RF}}$=10 dBm to the IDTs. The vertical (horizontal) dotted rectangle marks the transport channel formed by SAW$_1$ (SAW$_2$ or SAW$_3$).[]{data-label="Fig3"}](Figure_4.png){width="\columnwidth"}

The PL images of Figs. \[Fig3\](a)-\[Fig3\](c) have been recorded with the EXATs at the output ports in the OFF state, thus leading to the recombination of the transported IXs close to their gate electrodes. The combined action of long-range IX transport with electrostatic EXAT switching is exemplified in Fig. \[Fig3\](d). The image was recorded under the same conditions as Fig. \[Fig3\](c) except that EXAT$_6$ was turned ON by changing its gate bias. Under these conditions, the IXs are transported to the transistor source area. Flow control by the EXAT gate electrodes, which can isolate the sources from the common drain, becomes particularly important for the electric control of IX storage and recombination using the source bias.

Discussions and Conclusions {#Discussions_and_Conclusions}
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The total transport distance between the input and output ports in Fig. \[Fig3\](d) approaches 1000 $\mu$m, thus yielding IX lifetimes exceeding 380 ns. These transport distances, which are well beyond the state of the art in the field, are 