Natural mode entanglement as a resource for quantum communication

Area of Science:

• Quantum physics
• Atomic physics
• Quantum information science

Background:

• Particle-number entanglement exists between spatial modes in ultracold atomic gases.
• A superselection rule prevents coherent superpositions of different particle numbers, restricting mode entanglement use.

Purpose of the Study:

• To demonstrate that mode entanglement can be utilized for quantum communication despite the superselection rule.
• To provide schemes for dense coding and quantum teleportation using single massive particle mode entanglement.

Main Methods:

• Theoretical demonstration of dense coding and quantum teleportation protocols.
• Analysis of channel capacity with and without a shared reservoir.

Main Results:

• Mode entanglement of a single massive particle can be used for dense coding and quantum teleportation.
• Dense coding linear photonic channel capacity is achievable without a shared reservoir.
• Full quantum channel capacity is achieved when a coherent particle reservoir is shared.

Conclusions:

• The superselection rule does not prevent the use of mode entanglement for quantum communication.
• Novel schemes enable efficient quantum communication protocols in ultracold atomic gases.