Figure 1
APS/Alan Stonebraker

Figure 1: The atom-controlled optical switch consists of a bottle microresonator and two optical fibers. In the “on” position (top), photons from the bus fiber couple into the resonator and transfer out through the drop fiber. In the “off” position (bottom), a single atom flies into the evanescent field of the microresonator, destroying the cavity-mediated coupling between the fibers. Photons then maintain their path along the bus fiber.