Entanglement-Enhanced Optical Atomic Clocks

Abstract

Recent developments in atomic physics have enabled the experimental generation of many-body entangled states to boost the performance of quantum sensors beyond the Standard Quantum Limit (SQL). This limit is imposed by the inherent projection noise of a quantum measurement. In this perspective article, we describe the commonly used experimental methods to create many-body entangled states to operate quantum sensors beyond the SQL. In particular, we focus on the potential of applying quantum entanglement to state-of-the-art optical atomic clocks. In addition, we present recently developed time-reversal protocols that make use of complex states with high quantum Fisher information without requiring sub-SQL measurement resolution. We discuss the prospects for reaching near-Heisenberg limited quantum metrology based on such protocols.

8 pages, 7 figures, perspective article

References in corpus (16)

• An ${}^{27}$Al${}^{+}$ quantum-logic clock with systematic uncertainty below $10^{-18}$
• Sr lattice clock at 1x10^{-16} fractional uncertainty by remote optical evaluation with a Ca clock
• Twin matter waves for interferometry beyond the classical limit
• Fisher Information and entanglement of non-Gaussian spin states
• Searching for dilaton dark matter with atomic clocks
• Ultra-stable optical clock with two cold-atom ensembles
• Improved limit on a temporal variation of $m_p/m_e$ from comparisons of Yb${}^{+}$ and Cs atomic clocks
• Test of the Gravitational Redshift with Galileo Satellites in an Eccentric Orbit
• Spin squeezing of a cold atomic ensemble with the nuclear spin of one-half
• Near-Unitary Spin Squeezing in ${}^{171}$Yb
• Probing Interactions between Ultracold Fermions
• Direct limits on the interaction of antiprotons with axion-like dark matter
• Spin squeezing of atomic ensembles by multi-colour quantum non-demolition measurements
• Probing new intra-atomic force with isotope shifts
• Detuning Enhanced Cavity Spin Squeezing
• Cavity-enhanced non-destructive detection of atoms for an optical lattice clock

Cited by in corpus (16)

• Multi-qubit gates and Schrödinger cat states in an optical clock
• Entanglement-enhanced quantum metrology: from standard quantum limit to Heisenberg limit
• Combining critical and quantum metrology
• Multi-ensemble metrology by programming local rotations with atom movements
• GHZ protocols enhance frequency metrology despite spontaneous decay
• Demonstration of chronometric leveling using transportable optical clocks beyond laser coherence limit
• Variational quantum state preparation for quantum-enhanced metrology in noisy systems
• Optimal Ramsey interferometry with echo protocols based on one-axis twisting
• A hybrid method of generating spin-squeezed states for quantum-enhanced atom interferometry
• Dynamics of spin-momentum entanglement from superradiant phase transitions
• Enhancing Dynamic Range of Sub-Quantum-Limit Measurements via Quantum Deamplification
• Quantum Metrology via Floquet-Engineered Two-axis Twisting and Turn Dynamics
• Bayesian Frequency Metrology with Optimal Ramsey Interferometry in Optical Atomic Clocks
• Bosonic Entanglement and Quantum Sensing from Energy Transfer in two-tone Floquet Systems
• Efficient inference of quantum system parameters by Approximate Bayesian Computation
• Compact Fiber-Coupled Narrowband Two-Mode Squeezed Light Source