Harnessing non-Markovian dissipation to control quantum devices*

Nanodevices exploiting quantum effects are critically important elements of future quantum technologies (QT), but their real-world performance is strongly limited by decoherence arising from
local 'environmental' interactions. Compounding this, as devices become more complex, i.e. contain multiple functional units, the 'local' environments begin to overlap, creating the possibility
of environmentally mediated decoherence phenomena on new time-and-length scales. Such complex and inherently non-Markovian dynamics could present a challenge for scaling up QT, but -
on the other hand - the ability of environments to transfer 'signals' and energy might also enable
sophisticated spatiotemporal coordination of inter-component processes, as is suggested to happen
in biological nanomachines, like enzymes and photosynthetic proteins. Exploiting numerically exact many body methods (tensor networks) we study a general, fully quantum model that allows
us to explore how propagating environmental dynamics can instigate and direct the evolution of
spatially remote, non-interacting quantum systems. We demonstrate how energy dissipated into the
environment can be remotely harvested to create transient excited states, and also identify
how reorganisation triggered by system excitation can qualitatively and reversibly alter the 'downstream' kinetics of a functional site. With access to complete system-environment wave functions,
we elucidate the microscopic processes underlying these phenomena, providing new insight into how
they could be exploited for energy efficient quantum devices.