We propose a novel timelike quantum energy teleportation (QET) protocol within the 1+1 dimensional Nambu-Jona-Lasinio (NJL) model, an interacting fermionic field theory exhibiting spontaneous chiral symmetry breaking. By coupling localized Unruh-DeWitt detectors to the fermionic field, we demonstrate how an initial observer's measurement enables a second observer to extract energy at a later time using only classical information transfer. This protocol leverages the NJL vacuum's rich entanglement structure, driven by the chiral condensate, to facilitate energy transfer without physical particle transport. We derive the energy flows and explore the roles of measurement and time evolution and validate the protocol through quantum circuit simulations on a lattice-regularized NJL model. Our findings highlight the NJL model's potential as a platform for exploring QET in interacting quantum field theories and pave the way for experimental realizations on quantum hardware.
We propose a novel timelike quantum energy teleportation (QET) protocol within the 1+1 dimensional Nambu-Jona-Lasinio (NJL) model, an interacting fermionic field theory exhibiting spontaneous chiral symmetry breaking. By coupling localized Unruh-DeWitt detectors to the fermionic field, we demonstrate how an initial observer's measurement enables a second observer to extract energy at a later time using only classical information transfer. This protocol leverages the NJL vacuum's rich entanglement structure, driven by the chiral condensate, to facilitate energy transfer without physical particle transport. We derive the energy flows and explore the roles of measurement and time evolution and validate the protocol through quantum circuit simulations on a lattice-regularized NJL model. Our findings highlight the NJL model's potential as a platform for exploring QET in interacting quantum field theories and pave the way for experimental realizations on quantum hardware.
We establish a novel quantum protocol called Timelike Quantum Energy Teleportation (TQET) between two separated parties A and B, designed for transporting quantum energy across spacetime. The amount of energy gained through TQET is always greater than or equal to that obtained via natural time evolution for any spin chain where A and B are distinguishable. This protocol uses temporal and spatial quantum correlations between agents separated by space and time. The energy supplier injects energy into the system by measuring the ground state of a many-body system that evolves over time, while the distant recipient performs a conditional operation using feedback from the supplier. When Bob acts immediately after receiving Alice's outcome, the protocol reduces to conventional QET. We present a proof-of-concept demonstration in the Ising model using quantum simulations. TQET increases energy efficiency from approximately 3\% to around 40\%, representing over a 13-fold improvement compared to QET. Furthermore, we analyzed the relationship between entanglement in time and TQET, validating the role of temporal correlations in energy activation between agents across spacetime.
Quantum energy teleportation (QET) is a protocol that enables the extraction of positive energy from a local subsystem by exploiting ground-state entanglement and classical communication, without any physical carrier transporting energy between distant parties. In this work, we propose and analyze a QET protocol implemented in strongly driven atomic systems subjected to intense classical fields. We model a pair of interacting two-level atoms (or effective few-level systems) driven by a strong, time-dependent field and coupled via dipole–dipole or mediated interactions. The strong field creates a nontrivial, Floquet-engineered energy landscape and modifies the structure of ground-state and steady-state correlations. Within this setting, we construct local energy density operators and identify regimes in which negative local energy densities are dynamically generated and can be accessed via local measurements. We then formulate a QET protocol in which Alice performs a local measurement on her strongly driven atom, injects energy into the system, and sends the classical outcome to Bob, who performs a conditional local unitary on his distant atom to extract positive energy from the strongly driven environment. We derive explicit expressions for the teleported energy and analyze its dependence on driving strength, detuning, atom–atom coupling, and measurement parameters. Our results demonstrate that strong-field driving can enhance the amount of teleported power , extend the QET operating range to non-equilibrium Floquet regimes, and provide a feasible route toward realizing QET in tabletop atomic platforms driven by intense laser fields.
Quantum energy teleportation (QET) is, from the operational viewpoint of distant protocol users, energy transportation via local operations and classical communication. QET has various links to fundamental research fields including black-hole physics, the quantum theory of Maxwell's demon, and quantum entanglement in condensed-matter physics. However, the energy that has been extracted using a previous QET protocol is limited by the distance between two protocol users; the upper bound of the energy being inversely proportional to the distance. In this paper, we prove that introducing squeezed vacuum states with local vacuum regions between the two protocol users overcomes this limitation, allowing energy teleportation over practical distances.
In this article, we explore a feedback-control protocol in different quantum field theories (QFTs) to study the quantum correlation in nonunitary evolution of quantum systems. Traditional studies on QFTs focus on quantum entanglement of pure states under the unitary evolution, however, we examine quantum correlation in mixed states using quantum energy teleportation (QET), which is an energy transfer protocol by utilizing ground state entanglement, and introduce quantum discord as a measure. QET involves a midcircuit measurement, which disrupts pure state entanglement. Despite this, our analysis demonstrates that quantum discord maintains the correlation throughout the QET process. We conducted numerical analyses with benchmark models including the Nambu-Jona-Lasinio (NJL) model, revealing that quantum discord consistently acts as an order parameter for phase transitions. The model is extended in a way that it has both the chiral chemical potential and the chemical potential, which are useful to study the phase structures mimicking the chiral imbalance between left- and right- quarks coupled to the chirality density operator. In all cases we studied, the quantum discord behaved as an order parameter of the phase transition. Published by the American Physical Society 2024
Quantum energy teleportation (QET) has been proposed to overcome the restrictions of strong local passivity (SLP) and to facilitate energy transfer in quantum systems. Traditionally, QET has only been considered under strict constraints, including the requirements that the initial state be the ground state of an interacting Hamiltonian, that Alice's measurement commute with the interaction terms, and that entanglement be present. These constraints have significantly limited the broader applicability of QET protocols. In this work, we demonstrate that SLP can arise beyond these conventional constraints, establishing the necessity of QET in a wider range of scenarios for local energy extraction. This leads to a more flexible and generalized framework for QET. Furthermore, we introduce the concept of a "local effective Hamiltonian," which eliminates the need for optimization techniques in determining Bob's optimal energy extraction in QET protocols. As an additional advantage, the amount of energy that can be extracted using our new protocol is amplified to be 7.2 times higher than that of the original protocol. These advancements enhance our understanding of QET and extend its broader applications to quantum technologies. To support our findings, we implement the protocol on quantum hardware, confirming its theoretical validity and experimental feasibility.
Quantum Energy Teleportation (QET) exploits quantum entanglement and local operations with classical communication (LOCC) to transfer energy between distant locations without physically transporting the energy carrier. Previous demonstrations on superconducting hardware employed a two-qubit architecture and achieved a work extraction efficiency of approximately 11.7%. In this work, we propose a three-qubit QET protocol based on a novel Ising-model Hamiltonian satisfying the zero-mean-energy condition and the commutation and anti-commutation constraints required for QET. We investigate two complementary protocols. In the Single-Input Multiple-Output (SIMO) configuration, a single sender injects energy while two receivers jointly extract negative energy. Retaining all interaction terms, including the inter-receiver coupling, yields an honest work extraction efficiency of approximately 8--10%, comparable to the two-qubit implementation while distributing the extracted energy across two receivers. In the Multiple-Input Single-Output (MISO) configuration, two senders jointly inject energy through a single entangle-then-measure operation, and one receiver extracts the teleported energy. After subtracting the energy deposited directly into the receiver by the entangling operation, the net teleportation efficiency reaches 34--42%, substantially exceeding the two-qubit protocol while remaining consistent with energy conservation. These results show that extending QET to a three-qubit many-body system can significantly improve teleportation efficiency and provide a framework for studying energy transport, negative-energy distributions, and more complex quantum many-body dynamics.