Short-Distance Quantum Teleportation: Reducing Qubits, Boosting Communication Efficiency

Short-distance teleportation, a concept in quantum technology, involves transferring quantum states across short distances. This process reduces the number of qubits required in the entangled quantum channel, making it a promising area of research in quantum technology. A recent paper by researchers from the Indian Institute of Engineering Science and Technology Shibpur presents a short-distance teleportation protocol that allows an arbitrary three-qubit state to be transferred with the help of auxiliary qubits and a maximally entangled Bell-State. This development could have significant implications for the future of quantum technology.

What is Short-Distance Teleportation and Why is it Important?

Short-distance teleportation is a concept in quantum technology that involves the transfer of quantum states across short distances. This concept has gained relevance due to recent developments in quantum technology. The advantage of short-distance teleportation is that certain auxiliary qubits can be accessed and utilized by both the sender and the receiver. This reduces the requirement of the number of qubits in the entangled quantum channel, which would have otherwise been necessary.

The concept of teleportation protocols was originally applicable to a single qubit from the sender (Alice) to the receiver (Bob). This was introduced in the work of Bennett et al. Since then, there have been several versions of teleportation which apply to a large variety of quantum states. One such type of protocol is known as controlled teleportation protocol, in which the process of state transfer is executed under the supervision of a third party, known as the controller.

The role of the controller is to oversee and ensure the correct execution of the protocol. After being satisfied with the performances of the other parties involved in it, the controller performs an appropriate measurement and sends the measurement result to the potential receivers for the execution of the final steps. Controlled teleportation protocol was first introduced in the work of Karlsson and Bourennane, in which they achieved teleportation of an arbitrary qubit state via an entangled three-qubit state.

How Does Short-Distance Teleportation Work?

In a recent paper by Manoj Kumar Mandal, Binayak S Choudhury, and Plaban Saha from the Indian Institute of Engineering Science and Technology Shibpur, a short-distance teleportation protocol is presented. This protocol allows an arbitrary three-qubit state to be transferred with the help of auxiliary qubits and a maximally entangled Bell-State.

In the second part of the paper, a probabilistic short-distance protocol for the same arbitrary three-qubit state is introduced by using a non-maximally entangled Bell-state. The success probability of the protocol is calculated and its relation with the first protocol is discussed. A circuit diagram for the first protocol is presented and executed in the IBMQE platform.

Teleportation can also be performed by using a non-maximal entangled channel, in which case the process of state transfer succeeds only probabilistically. Such processes are called probabilistic quantum teleportation protocols, which were initiated in the work of Li et al. In this work, a non-maximally entangled Bell state as a quantum entangled channel was used.

What are the Advantages of Short-Distance Teleportation?

The advantage of short-distance teleportation is that some auxiliary qubits can be commonly accessed by the different parties due to the nearness of their physical positions. This phenomenon allows for the reduction in the number of qubits in the quantum channel. Since multi-qubit entangled states are difficult to produce, any possible reduction in the number of qubits in the entangled channel is a welcome feature in the communication process.

Tan and Han first presented a short-distance teleportation protocol of an arbitrary two-qubit state. This approach utilizes a Bell state as the quantum channel and an auxiliary particle in the ground state 0. In the protocol, it is necessary for both the sender and receiver to conduct unitary transformations on a shared auxiliary particle. For this reason, the auxiliary particle has to be physically close and accessible to both the sender and the receiver.

What are the Future Implications of Short-Distance Teleportation?

The future implications of short-distance teleportation are vast. With the recent development of quantum technology, the transfer of quantum states is necessary across short distances. This is especially true in situations where auxiliary qubits can be commonly accessed by different parties due to their physical proximity.

The reduction in the number of qubits in the quantum channel is a significant advantage in the communication process. As multi-qubit entangled states are difficult to produce, any reduction in the number of qubits is beneficial. This makes short-distance teleportation a promising area of research in quantum technology.

In conclusion, short-distance teleportation is a significant development in quantum technology. The ability to transfer quantum states across short distances with reduced qubits is a major advancement. The work of Manoj Kumar Mandal, Binayak S Choudhury, and Plaban Saha provides valuable insights into this area of research and opens up new possibilities for future developments in quantum technology.