Improving resilience of the Quantum Gravity Induced Entanglement of Masses (QGEM) to decoherence using 3 superpositions

Abstract

Recently a protocol called quantum gravity induced entanglement of masses (QGEM) that aims to test the quantum nature of gravity using the entanglement of 2 qubits was proposed. The entanglement can arise only if the force between the two spatially superposed masses is occurring via the exchange of a mediating virtual graviton. In this paper, we examine a possible improvement of the QGEM setup by introducing a third mass with an embedded qubit, so that there are now 3 qubits to witness the gravitationally generated entanglement. We compare the entanglement generation for different experimental setups with 2 and 3 qubits and find that a 3-qubit setup where the superpositions are parallel to each other leads to the highest rate of entanglement generation within $\tau =5$ s. We will show that the 3-qubit setup is more resilient to the higher rate of decoherence. The entanglement can be detected experimentally for the 2-qubit setup if the decoherence rate $\gamma$ is $\gamma <0.11$ Hz compared to $\gamma <0.16$ Hz for the 3-qubit setup. However, the introduction of an extra qubit means that more measurements are required to characterize entanglement in an experiment. We conduct experimental simulations and estimate that the 3-qubit setup would allow detecting the entanglement in the QGEM protocol at a $99.9\%$ certainty with $O(10^4)-O(10^5)$ measurements when $\gamma \in [0.1,0.15]$ Hz. Furthermore, we find that the number of needed measurements can be reduced to $O(10^3)-O(10^5)$ if the measurement schedule is optimised using joint Pauli basis measurements. For $\gamma >0.06$ Hz the 3-qubit setup is favourable compared to the 2-qubit setup in terms of the minimum number of measurements needed to characterize the entanglement. Thus, the proposed setup here provides a promising new avenue for implementing the QGEM experiment.

20 pages, 16 figures, 5 tables; accepted version in PRA, fixed references

References in corpus (26)

• Entanglement detection
• A Spin Entanglement Witness for Quantum Gravity
• Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
• Locality & Entanglement in Table-Top Testing of the Quantum Nature of Linearized Gravity
• Efficient quantum measurement of Pauli operators in the presence of finite sampling error
• Observable quantum entanglement due to gravity
• Quantum Gravity Witness via Entanglement of Masses: Casimir Screening
• Realization of a complete Stern-Gerlach interferometer: Towards a test of quantum gravity
• Large Quantum Delocalization of a Levitated Nanoparticle using Optimal Control: Applications for Force Sensing and Entangling via Weak Forces
• Mechanism for the quantum natured gravitons to entangle masses
• Non-Gaussianity as a signature of a quantum theory of gravity
• Motional Dynamical Decoupling for Matter-Wave Interferometry
• Using an atom interferometer to infer gravitational entanglement generation
• Minimizing State Preparations in Variational Quantum Eigensolver by Partitioning into Commuting Families
• Decoherence effects in non-classicality tests of gravity
• Witnessing the non-classical nature of gravity in the presence of unknown interactions
• Efficient evaluation of quantum observables using entangled measurements
• Gravity-induced entanglement in optomechanical systems
• Relative Acceleration Noise Mitigation for Nanocrystal Matter-wave Interferometry: Application to Entangling Masses via Quantum Gravity
• Qudits for Witnessing Quantum Gravity Induced Entanglement of Masses Under Decoherence
• Entanglement and decoherence of massive particles due to gravity
• Two-slit diffraction with highly charged particles: Niels Bohr's consistency argument that the electromagnetic field must be quantized
• Signatures of the quantum nature of gravity in the differential motion of two masses
• $T\bar{T}$ deformation of random matrices
• $O(N^3)$ Measurement Cost for Variational Quantum Eigensolver on Molecular Hamiltonians
• Massive Spatial Qubits for Testing Macroscopic Nonclassicality and Casimir Induced Entanglement

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• Entanglement Witness for the Weak Equivalence Principle
• Entanglement based tomography to probe new macroscopic forces
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• Quantum entanglement of masses with non-local gravitational interaction
• Mass-independent scheme for enhancing spatial quantum superpositions
• Decoherence of a matter-wave interferometer due to dipole-dipole interactions
• Relaxation of experimental parameters in a Quantum-Gravity Induced Entanglement of Masses Protocol using electromagnetic screening
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• Distinguishing Jordan and Einstein frames in gravity through entanglement
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• Internal decoherence in nano-object interferometry due to phonons
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• Gravitational Harmonium: Gravitationally Induced Entanglement in a Harmonic Trap
• Testing Whether Gravity Acts as a Quantum Entity When Measured
• Amplification of Gravitationally Induced Entanglement
• Gravitational decoherence by the apparatus in the quantum-gravity induced entanglement of masses
• Feasible generation of gravity-induced entanglement by using optomechanical systems
• The generation rate of quantum gravity induced entanglement with multiple massive particles
• Quantum signature of gravity in optomechanical systems with conditional measurement
• Signatures of Quantum Gravity in the Gravitational Self-Interaction of Photons
• Phonon-induced contrast in a matter-wave interferometer
• Inertial Torsion Noise in Matter-Wave Interferometers for Gravity Experiments
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• Magnetic noise in macroscopic quantum spatial superposition
• Exponentially enhanced gravitationally induced entanglement between quantum systems with a two-phonon drive
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• Entanglement witnesses mediated via axionLike particles
• Gravity induced entanglement of multiple massive particles with large spin
• Quantum Gravity Induced Entanglement of Masses With Extra Dimensions