Demonstration of Controlled Quantum Teleportation for Discrete Variables on Linear Optical Devices

Abstract

We report an experimental implementation of tripartite controlled quantum teleportation on the quantum optical devices. The protocol is performed through bi-and tripartite entangled channels of discrete variables and qubits encoded in polarization of individual photons. The experimental results demonstrate successful controlled quantum teleportation with a fidelity around 83%, well above the classical limit. By realizing the controlled quantum teleportation through biseparable state, we show that tripartite entangled is not a necessary resource for controlled quantum teleportation and the controller's capability to allow or prohibit the teleportation cannot be considered to be a manifestation of tripartite entanglement. These results open new possibilities for further application of controlled quantum teleportation by lowering teleportation channel's requirements.Introduction.-Quantum teleportation is considered as one of the major protocols in quantum information science. By exploiting the physical resource of entanglement, quantum teleportation has played a prominent role in the development of quantum information theory [1][2][3][4][5] and represents a fundamental ingredient to the progress of many quantum technologies such as quantum gate teleportation [6], quantum repeaters [7,8], measurementbased quantum computing [9], port-based teleportation [10] and quantum network teleportation (QTN) [11][12][13]. Teleportation has also been used as a quantum simulator for 'extreme' phenomena, such as closed timelike curves and the grandfather paradox [14].Quantum teleportation, first proposed by Bennett et al.[1], is a scheme of quantum information processing which allows the transfer of a quantum state between remote physical systems without physical transfer of the information carrier. Specifically, an unknown quantum state of a physical system is measured and subsequently reconstructed at a remote location through the use of classical communication and quantum entanglement [15,16]. Without entanglement, such quantum state transfer would not be possible within the laws of quantum mechanics. For that reason, quantum teleportation is thought of as the quantum information protocol which clearly demonstrates the character of quantum entanglement as a resource.To date, quantum teleportation has been achieved and studied in many different systems, including photonic systems, nuclear magnetic resonance, optical modes, trapped atoms and solid-state systems (see [17] and references therein). Naturally, most attention has been focused on teleporting the state on long-distance [18,19] with the recent satellite-based implementations [20]. However, even though quantum teleportation is a typically bipartite process, it can be extended to multipartite quantum protocols which have not been thoroughly studied yet. Such multipartite protocols are expected to form fundamental components for larger-scale quantum

Enhancement of the entanglement generation via randomly perturbed series of external pulses in a nonlinear Bose–Hubbard dimer

“…Another group of possible applications of the entangled states is related to the proposals of quantum internet [21]. In particular, quite recently, the experiment which can lead to the construction of quantum routers was performed and presented in [22]. At this point, one should mention the successful quantum teleportation from the surface of the Earth to the satellite [23], which opens new perspectives in the development of quantum technologies.…”

Quantum teleportation is a reversal of quantum measurement

“…Quantum teleportation is at the core of quantum information technologies [1][2][3][4]. Ever since the seminal work by Bennett et al [5], teleportation has been demonstrated in various physical platforms [6][7][8][9][10][11][12][13][14][15] and many different protocols have been proposed to date [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. Recently, developments have been directed to its potential applications for long-distance quantum communications [31][32][33][34][35], inter-chip communications [36] and other versatile functionalities toward scalable quantum architectures [37][38][39].…”

“…In this respect, applying a unitary operation at the receiver's station may not always be optimal in practice. However, existing teleportation protocols to date conventionally limit Bob's operation to unitary [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30], which would also significantly limit the fault-tolerance of quantum teleportation.…”

“…We define a quantum teleportation as transmitting an unknown quantum state by disturbing it with measurement at one location and reconstructing it with a certain operation at another location, where two locations are connected via quantum entanglement. This not only encompasses all existing teleportation protocols [5,[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] but generalizes the scope of teleportation as we describe below.…”

“…A remaining step to complete the teleportation is applying an appropriate operation to recover ρ. Note that this operation has been limited to a conditional unitary operation in previous protocols [5,[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] as illustrated in Fig. 1 (a).…”