Energy cost of entanglement extraction from quantum fields*

In quantum information science, entanglement provides a valuable resource that can be used for communication, cryptography and quantum teleportation. The ground state of relativistic field theories is spatially highly entangled, so it is natural to ask if two separated parties, Alice and Bob, can extract some of this entanglement for their own use. Indeed, this can be accomplished by interacting locally with the field and thereby inevitably increasing the energy of the state. In this talk, I present lower bounds for the energy cost of entanglement extraction (measured in entropy) per mode in scalar quantum field theories and compare them to a concrete scenario where Alice and Bob are both localized in spacetime.