Teleportation Research Articles

Experimental Virtual Distillation of Entanglement and Coherence.

Noise is, in general, inevitable and detrimental to practical and useful quantum communication and computation. Under the resource theory framework, resource distillation serves as a generic tool to overcome the effect of noise. Yet, conventional resource distillation protocols generally require operations on multiple copies of resource states, and strong limitations exist that restrict their practical utilities. Recently, by relaxing the setting of resource distillation to only approximating the measurement statistics instead of the quantum state, a resource-frugal protocol, "virtual resource distillation," is proposed, which allows more effective distillation of noisy resources. Here, we report its experimental implementation on a photonic quantum system for the distillation of quantum coherence (up to dimension four) and bipartite entanglement. We show the virtual distillation of the maximal superposed state of dimension four from the state of dimension two, an impossible task in conventional coherence distillation. Furthermore, we demonstrate the virtual distillation of entanglement with operations acting only on a single copy of the noisy Einstein-Podolsky-Rosen (EPR) pair and showcase the quantum teleportation task using the virtually distilled EPR pair with a significantly improved fidelity of the teleported state. These results illustrate the feasibility of the virtual resource distillation method and pave the way for accurate manipulation of quantum resources with noisy quantum hardware.

Short-Distance Bidirectional Teleportation of High-Dimensional Arbitrary Single-Qudit States

Short-Distance Bidirectional Teleportation of High-Dimensional Arbitrary Single-Qudit States

Effects of quantum noise on teleportation of arbitrary two-qubit state via five-particle Brown state

Abstract We propose a new protocol for quantum teleportation (QT) which adopts the Brown state as the quantum channel. This work focuses on the teleportation of a single unknown two-qubit state via a Brown state channel in an ideal environment. To validate the effectiveness of our proposed scheme, we conduct experiments by using the quantum circuit simulator Quirk. Furthermore, we investigate the effects of four noisy channels, namely, the phase damping noise, the bit-flip noise, the amplitude damping noise, and the phase-flip noise. Notably, we employ Monte Carlo simulation to elucidate the fidelity density under various noise parameters. Our analysis demonstrates that the fidelity of the protocol in a noisy environment is influenced significantly by the amplitude of the initial state and the noise factor.

Teleportation of Post-Selected Quantum States

Teleportation allows Alice to send a pre-prepared quantum state to Bob using only pre-shared entanglement and classical communication. Here we show that it is possible to teleport a state which is also post-selected. Post-selection of a state Φ means that after Alice has finished her experiment she performs a measurement and only keeps runs of the experiment where the measurement outcome is Φ. We also demonstrate pre and post-selected port-based teleportation. Finally we use these protocols to perform instantaneous non-local quantum computation on pre and post-selected systems, and significantly reduce the entanglement required to instantaneously measure an arbitrary non-local variable of spatially separated pre and post-selected systems.

Dynamics of quantum coherence and nonlocality of a two-spin system in the chemical compass.

In this paper a system consisting of two electron spins has been prepared initially in a singlet state using the chemical compass model is considered. It is assumed that each electron spin interacts symmetrically and/or asymmetrically with its respective private nuclear environment in the presence of an external magnetic field. We discussed the effect of the interaction parameters and the external magnetic field on some quantifiers of quantum correlations as entanglement, coherence, Bell inequality, as well as the steerability inequality. It is shown that within a certain range of external magnetic fields, the quantum coherence and entanglement behave similarly. The Bell and the steerable inequalities predicted a similar behavior for symmetric and asymmetric interactions. Moreover, as one increases the external magnetic field, the lower bounds of both inequalities have improved. The usefulness of using the spin state as quantum channel to teleport a two-qubit system has examined where the Bell inequality could be above its classical bounds by controlling the interaction parameters. It is shown that by tuning the coupling parameters the fidelity of the teleported state exceeds the classical bounds, as well as the long-lived stationary fidelity could be achieved during the interaction time.

Faithful quantum teleportation through common and independent qubit-noise configurations and multi-parameter estimation in the output of teleported state

Quantum teleportation allows the transmission of unknown quantum states over arbitrary distances. This paper studies quantum teleportation via two non-interacting qubits coupled to local fields and Ornstein Uhlenbeck noise. We consider two different qubit-noise configurations, i.e., common qubit-noise interactions and independent qubit-noise interactions. We introduce a Gaussian Ornstein Uhlenbeck process to take into account the noisy effects of the local external fields. Furthermore, we address the intrinsic behavior of classical fields toward single- and two-qubit quantum teleportation as a function of various parameters. Additionally, using a quantum estimation theory, we study single- and multi-parameter estimation of the teleported state output for single and two-qubit quantum teleportation scenarios. One important application of this work is obtaining more valuable information in quantum remote sensing.

Multi-hop quantum teleportation of a N-qubit quantum state by using cluster state

In this study, a new multi-hop quantum teleportation is investigated for transferring a N-qubit quantum state which compared with previous protocols can give a more efficient data teleportation. In proposed scheme, quantum channels among adjacent nodes are built based on ([Formula: see text])-qubit cluster state. The source node and all intermediate nodes perform measurement and announce outcome results to the destination node through the classical channel. Finally, the destination node can recover the desired quantum state by applying the appropriate unitary operators on the state it has. Also, in order to explain the details of this scheme, the multi-hop quantum teleportation of 6-qubit quantum state by using 7-qubit cluster state investigate and calculate its efficiency.

Analysis of continuous-variable quantum teleportation enhanced by measurement-based noiseless quantum amplification.

Continuous-variable quantum teleportation enables deterministic teleportation of quantum states of optical modes. However, the state transfer is imperfect and limited by the amount of squeezing in the shared two-mode entangled state. Recently, it has been proposed and experimentally demonstrated that the performance of continuous-variable teleportation can be conditionally improved using a measurement-based noiseless quantum amplification [J. Zhao et al., Nat. Commun.14, 4745 (2023)10.1038/s41467-023-40438-z]. An inverse Gaussian filter with sufficiently high cut-off is applied to outcomes of the continuous-variable Bell measurement, which can increase the fidelity of state teleportation and the cost of making the protocol probabilistic. Here we provide a detailed theoretical analysis of this protocol and discuss its effects and limitations. We focus on teleportation of classes of Gaussian states with fixed covariance matrix and variable displacement. The measurement-based noiseless amplification conditionally improves the precision of estimation of the coherent displacement of the teleported state from the outcomes of continuous-variable Bell measurement. Therefore, more information about the teleported state is revealed and unity-gain teleportation becomes possible with a lower added thermal noise as compared to deterministic teleportation.

Controlled cyclic quantum teleportation of unknown single-qutrit states

In order to explore multi-directional quantum communication in a three-dimensional (3D) system, five-, seven- and [Formula: see text]-qutrit entangled states are constructed by 3D-Hadamard gates and 3D-controlled-NOT gates in this paper. Then a new scheme of controlled bidirectional quantum teleportation (QT) via five-qutrit entangled channel is proposed, where two observers can exchange their unknown single-qutrit states at the same time under the control of the supervisor. Along this mental, we propose a novel theoretical scheme to fulfil four-party controlled cyclic QT by using a seven-qutrit entangled state as the quantum channel, in which Alice can teleport an arbitrary unknown single-qutrit state to Bob, Bob can transmit an arbitrary single-qutrit state to Charlie, at the same time, Charlie can also teleport an arbitrary unknown single-qutrit state to Alice with the permission of the supervisor. In these schemes, only specific two-qutrit 3D-Bell state measurements, single-qutrit 3D-Z-basis measurements and suitable 3D-Weyl operators are needed, which can be implemented in physics easily. Moreover, the proposed four-party controlled cyclic scheme can be generalized into the case containing [Formula: see text] ([Formula: see text]) observers by using a [Formula: see text]-qutrit entangled channel. Analysis shows that the success probability of our schemes can reach 1. Through detailed discussion, we find that the security of our schemes and the control power of the supervisors can be guaranteed, and the intrinsic efficiency of the proposed schemes is relatively high.

Quantum teleportation of a two-qubit arbitrary entangled state with four-qubit cluster state

Based on the four-qubit cluster state as quantum channel, we put forward a novel scheme for teleporting a two-qubit arbitrary entangled state. The necessary quantum operations for accomplishing the task are two controlled-not gate operations, one controlled-phase gate operation, four single-qubit measurements and two single-qubit transformed operations. They are easily achievable with current experimental techniques. Besides, the present scheme is deterministic because its probability of success is 100% .

Symmetric Cyclic Controlled Quantum Teleportation of Three-Qubit State by a nineteen-Qubit Entangled State

Symmetric Cyclic Controlled Quantum Teleportation of Three-Qubit State by a nineteen-Qubit Entangled State

Cavity‐Assisted Atomic External Momenta State Teleportation

AbstractThe quantized momentum eigenstates of neutral atoms offer high resistance to decoherence and thus suggests a viable alternative for quantum informatics tasks including teleportation. In this work, a scheme is suggested to teleport an unknown superposition of two distinct external momentum states of a neutral atom onto the similar momentum states of a distant atom at the receiving end through the off‐resonant atomic Bragg diffraction (ABD). In order to teleport this unknown state from the sender, that is, Alice, to the receiver, that is, Bob, a pre‐existing entangled link formed through a high‐Q cavity at Alice's end and momentum states of a neutral atom at the Bob's end are utilized. Further, while citing the realistic experimental parameters, it is demonstrated that the proposal can easily be implemented experimentally under the prevailing cavity‐QED atom‐field research scenario. The proposal is also generalized to cover the teleportation of the multipartite entangled momenta states and the case of multipartite GHZ entangled states is elucidated in details. However, the procedure is generic and can be extended to cover the teleportation schematics for any arbitrary atomic momenta states.

BERT-based tourism named entity recognition: making use of social media for travel recommendations.

Social media has become a massive encyclopedia of almost anything due to its content richness. People tell stories, write comments and feedback, and share knowledge through social media. The information available on social media enables 'clueless' travelers to get quick travel recommendations in the tourism sector. Through a simple query, such as typing 'places to visit in Bali', travelers can get many blog articles to help them decide which places of interest to visit. However, doing this reading task without a helper can be overwhelming. To overcome this problem, we developed Bidirectional Encoder Representations from Transformers (BERT)-based tourism named entity recognition system, which is used to highlight tourist destination places in the query result. BERT is a state-of-the-art machine learning framework for natural language processing that can give a decent performance in various settings and cases. Our developed tourism named entity recognition (NER) model specifies three different tourist destinations: heritage, natural, and purposefully built (man-made or artificial). The dataset is taken from various tourism-related community articles and posts. The model achieved an average F1-score of 0.80 and has been implemented into a traveling destination recommendation system. By using this system, travelers can get quick recommendations based on the popularity of places visited in the query frame. Based on the survey that we conducted to target respondents who have never visited and have no or limited knowledge about tourist attractions in some example cities, their average interest level from the recommendation results is higher than four on a scale of 1 to 5. Thus, it can be considered a good recommendation. Furthermore, the NER model performance is comparable to another related research.

Probing teleported quantum correlations in a two-qubit system inside a coherent field

This paper investigates the impact of dipole interactions and the initial quantum state configurations within a quantum system on teleported quantum correlations involving a pair of qubits embedded in a single-mode field. The analysis encompasses an exploration of non-separability, steerability, non-locality, and steered coherence of the teleported state, considering different initial Bell states for the two-qubit channel. The initial atomic setting state primarily influences the teleported quantum correlations. The study highlights that dipole interaction exert a substantial effect on both the maximum and minimum values of quantum correlations. Furthermore, increasing this interaction demonstrates the potential to enhance control over the decay of correlations induced by the detuning parameter.

Teleportation of superposed nonlinear coherent states

In this paper, we study the teleportation of nonlinear coherent cat states assuming even and odd nonlinear quasi-Bell states as the channel. Odd nonlinear quasi-Bell states are shown to be maximally entangled independent of the coherent parameter and also nonlinear function but the entanglement of the even nonlinear coherent states depends on the parameters involved. Subsequently, the teleportation probability is evaluated for some nonlinear functions. Our research reveals that when even and odd nonlinear quasi-Bell states are assumed as the quantum channel, the probabilities for successful teleportation are oppositely varied by increasing coherent parameter. For the special case of nonlinear harmonious states, the teleportation probability is a decreasing (increasing) function of the coherent parameter if even (odd) nonlinear quasi-Bell state is used as the channel.

Huge Fast Spacecraft Travelling Our Solar System

Can you imagine a large space system leaving from an Earth space elevator in excess of 12.34 km/sec, ensuring quick travel within our solar system? How about if it had an additional 10 km/sec assist from a slingshot release with the ability to gain another 15 km/sec by doing gravity assists along the way? The total concept being discussed is fast enough to allow travelling around our solar system within months instead of decades. However, there is more for those seeking answers beyond Earth – how about the ability to send multi-hundreds of tonnes along this path in a huge space system with fuel for rendezvous and landing along the way? How? Forget the Rocket Equation! You assemble a large spacecraft above the gravity well of the Earth, add velocity to it by virtue of the Earth’s rotation and then release it with extra velocity as if from a giant slingshot. An extra-long space elevator could achieve these goals by 2038. This story should be told as part of future opportunities for space exploration and science. Solar system travel, and even into interstellar regions, becomes reality with space elevators designed to assemble massive satellites and enable high velocity releases. Keywords: Space elevators, Neptune, Apex Anchor, Interplanetary

A Scheme for Quantum Teleportation and Remote Quantum State Preparation of IoT Multiple Devices.

With the continuous development of the Internet of Things (IoT) technology, the industry's awareness of the security of the IoT is also increasing, and the adoption of quantum communication technology can significantly improve the communication security of various devices in the IoT. This paper proposes a scheme of controlled remote quantum state preparation and quantum teleportation based on multiple communication parties, and a nine-qubit entanglement channel is used to achieve secure communication of multiple devices in the IoT. The channel preparation, measurement operation, and unitary operation of the scheme were successfully simulated on the IBM Quantum platform, and the entanglement degree and reliability of the channel were verified through 8192 shots. The scheme's application in the IoT was analyzed, and the steps and examples of the scheme in the secure communication of multiple devices in the IoT are discussed. By simulating two different attack modes, the effect of the attack on the communication scheme in the IoT was deduced, and the scheme's high security and anti-interference ability was analyzed. Compared with other schemes from the two aspects of principle and transmission efficiency, it is highlighted that the advantages of the proposed scheme are that it overcomes the single fixed one-way or two-way transmission protocol form of quantum teleportation in the past and can realize quantum communication with multiple devices, ensuring both security and transmission efficiency.

Investigating Imperfect Cloning for Extending Quantum Communication Capabilities.

Quantum computing allows the implementation of powerful algorithms with enormous computing capabilities and promises a secure quantum Internet. Despite the advantages brought by quantum communication, certain communication paradigms are impossible or cannot be completely implemented due to the no-cloning theorem. Qubit retransmission for reliable communications and point-to-multipoint quantum communication (QP2MP) are among them. In this paper, we investigate whether a Universal Quantum Copying Machine (UQCM) generating imperfect copies of qubits can help. Specifically, we propose the Quantum Automatic Repeat Request (QARQ) protocol, which is based on its classical variant, as well as to perform QP2MP communication using imperfect clones. Note that the availability of these protocols might foster the development of new distributed quantum computing applications. As current quantum devices are noisy and they decohere qubits, we analyze these two protocols under the presence of various sources of noise. Three major quantum technologies are studied for these protocols: direct transmission (DT), teleportation (TP), and telecloning (TC). The Nitrogen-Vacancy (NV) center platform is used to create simulation models. Results show that TC outperforms TP and DT in terms of fidelity in both QARQ and QP2MP, although it is the most complex one in terms of quantum cost. A numerical study shows that the QARQ protocol significantly improves qubit recovery and that creating more clones does not always improve qubit recovery.

Bi-directional quantum teleportation of GHZ-like states

In this paper, we propose a method through which [Formula: see text]-qubit states can simultaneously be bi-directionally transmitted between two users. We assume that Alice and Bob, the legitimate users, each have a [Formula: see text]-qubit GHZ-like state and want to teleport it to the other party. Also, a four-qubit cluster state plays the role of the quantum channel of this bi-directional quantum teleportation. The protocol is based on the method that at first, each user, through a series of [Formula: see text] gates, converts the [Formula: see text]-qubit state into a single qubit and some [Formula: see text] qubits. Then, by means of the Bell state measurement and proper operation, the single qubit state is transferred over the channel between the two sides. By re-applying the [Formula: see text] gates on the transmitted qubits and auxiliary [Formula: see text] states, each user reconstructs the initial GHZ-like state. Finally, we investigate the effects of some kind of noises on the density matrix of the channel due to its interaction with the environment and present a method to protect the channel against the bit-flip error.

Quantum teleportation of W-type states in the presence of a controller

In this paper, we discuss a proposal for the transfer of states belonging to the W-type states by executing a controlled teleportation protocol. A 7-qubit quantum entangled resource shared between the sender, receiver and controller is utilized in this protocol. The scheme proposed here is a perfect communication scheme where the task of quantum state transfer is performed with certainty. Further, a protocol for the generation of the quantum resource used here is designed and run on IBM platform. Additionally, we consider the effect of four types of noises, namely, amplitude-damping noise, bit-flip noise, phase-flip noise and phase-damping noise on our protocol. The efficiency of the protocol is compared with other similar protocols which shows that the present one is better performing.