Solid-State Quantum Battery

Quantum batteries should have faster charging time due to the quantum entanglement among the units. The units are all coupled to a common quantized electromagnetic mode, and photons from the energy source mediate a long-range interaction between units, generating entanglement among them.

The enhancement increases as the number of units increases (specifically, when a quantum battery consists of N units, the quantum advantage scales as the square root of N).

They will be investigating the tradeoff between the quantum battery’s charging power and its energy storage capacity.

Quantum information theorems state that it is possible to exploit collective quantum resources to greatly enhance the charging power of quantum batteries (QBs) made of many identical elementary units. Researchers present and solve a model of a QB that can be engineered in solid-state architectures. It consists of two-level systems coupled to a single photonic mode in a cavity. They contrast this collective model (“Dicke QB”), whereby entanglement is genuinely created by the common photonic mode, to the one in which each two-level system is coupled to its own separate cavity mode (“Rabi QB”). By employing exact diagonalization, they demonstrate the emergence of a quantum advantage in the charging power of Dicke QBs.