Quantum communication through devices with indefinite input-output direction

Quantum communication through devices with indefinite input-output direction

Blog Article

Certain quantum devices, such as half-wave plates and quarter-wave plates in quantum optics, are bidirectional, meaning that the roles of their input and output ports can be exchanged.Bidirectional devices can be used in a forward mode and a backward mode, corresponding to two opposite choices of the input-output direction.They can also be used in a coherent superposition of the forward and backward modes, giving rise to new operations with indefinite input-output direction.

In this work we explore the potential of input-output indefiniteness for the transfer of classical and quantum information through noisy channels.We first formulate a model of communication from a read more sender to a receiver via a noisy channel used in indefinite input-output direction.Then, we show that indefiniteness of the input-output direction yields advantages over standard communication protocols in which the given noisy channel is miracle academy clothing used in a fixed input-output direction.

These advantages range from a general reduction of noise in bidirectional processes, to heralded noiseless transmission of quantum states, and, in some special cases, to a complete noise removal.The noise reduction due to input-output indefiniteness can be experimentally demonstrated with current photonic technologies, providing a way to investigate the operational consequences of exotic scenarios characterised by coherent quantum superpositions of forward-time and backward-time processes.