Quantum register of fermion pairs

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Information Science
• Condensed Matter Physics

Background:

• Quantum control of individual particle motion is crucial for atomic clocks and quantum information processing.
• Motional coherence of single particles is fragile and susceptible to environmental noise.
• Naturally robust motional coherence is often observed in pairs of particles, such as electrons in helium or Cooper pairs.

Purpose of the Study:

• To demonstrate long-lived motional coherence and entanglement of paired fermionic atoms.
• To realize a robust qubit based on the common and relative motion of atom pairs.
• To explore methods for universal control of this novel motional qubit.

Main Methods:

• Utilizing an optical lattice array to trap pairs of fermionic atoms.
• Exploiting exchange symmetry to protect the motional qubit from environmental noise.
• Modulating interatomic interactions for qubit control.

Main Results:

• Observation of long-lived quantum coherence exceeding ten seconds for atom pairs.
• Demonstration of a robust motional qubit protected by exchange symmetry.
• The qubit's energy is insensitive to confining potential noise and depends only on atomic mass and lattice wavelength.

Conclusions:

• Paired fermionic atoms in optical lattices offer a robust platform for quantum information processing.
• The demonstrated methods enable programmable quantum simulators and precision metrology.
• This work advances the development of digital quantum computation using fermion pairs.