Demonstration of entanglement-enhanced phase estimation in solid

Area of Science:

• Quantum Metrology
• Quantum Information Science
• Solid-State Physics

Background:

• Precise parameter estimation is fundamental across scientific and technological domains.
• Classical measurement repetition reduces statistical error proportionally to the square root of repetitions, as per the central limit theorem.
• Quantum parameter estimation offers potential for enhanced statistical precision beyond classical methods.

Purpose of the Study:

• To implement and demonstrate entanglement-enhanced phase estimation in a solid-state system at room temperature.
• To showcase the use of quantum resources for improved measurement precision.
• To validate the theoretical expectation of uncertainty reduction through entanglement.

Main Methods:

• Utilized a solid-state system comprising a nitrogen-vacancy (NV) center electron spin and a proximal carbon-13 (13C) nuclear spin in pure diamond.
• Implemented entanglement between these two distinct physical qubits.
• Performed super-resolving phase measurements using the entangled qubit system.

Main Results:

• Achieved the first room-temperature implementation of entanglement-enhanced phase estimation in a solid-state system.
• Demonstrated a super-resolving phase measurement using two entangled qubits (NV electron spin and 13C nuclear spin).
• Experimental data confirmed a reduction in uncertainty when utilizing entanglement, aligning with theoretical predictions.

Conclusions:

• The study presents an elemental demonstration of quantum metrology outperforming classical procedures.
• Entanglement serves as a valuable resource for enhancing phase estimation precision in solid-state systems.
• This work paves the way for practical applications of quantum-enhanced sensing and metrology.