Experimental Demonstration of Quantum Tunneling in IBM Quantum Computer

Seth

Das

et al. 2019

Self Cite

Quantum communication is a secure way to transfer quantum information and to communicate with legitimate parties over distant places in a network. Although communication over a long distance has already been attained, technical problem arises due to unavoidable loss of information through the transmission channel. Quantum repeaters can extend the distance scale using entanglement swapping and purification scheme. Here we demonstrate the working of a quantum repeater by the above two processes. We use IBM's real quantum processor 'ibmqx4' to create two pair of entangled qubits and design an equivalent quantum circuit which consequently swaps the entanglement between the two pairs. We then develop a novel purification protocol which enhances the degree of entanglement in a noisy channel that includes combined errors of bit-flip, phase-flip and phase-change error. We perform quantum state tomography to verify the entanglement swapping between the two pairs of qubits and working of the purification protocol. *

Section: Introductionmentioning

confidence: 99%

Demonstration of entanglement purification and swapping protocol to design quantum repeater in IBM quantum computer

Seth

Das

et al. 2019

Self Cite

“…IBM Q is a superconducting qubit based operating system which offers open global access to a wide class of researchers and has found significant applications in an user friendly interface [24]. Violation of CHSH inequality [24] and Mermin's inequality for GHZ state [21], experimental realization of quantum cheque [16], demonstrations of non-Abelian braiding of Majorana modes [25], verification of quantum algorithms [27,28], testing error correction codes [26,29], building of a quantum repeater [30], quantum simulation [31,32], fidelity improvement [33] are the examples of a few tasks which have been imple-mented successfully.…”

Section: Introductionmentioning

confidence: 99%

Experimental demonstration of the violations of Mermin’s and Svetlichny’s inequalities for W and GHZ states

Swain

Rai

et al. 2019

Self Cite

Violation of Mermin's and Svetlichny's inequalities can rule out the predictions of local hidden variable theory and can confirm the existence of true nonlocal correlation for n-particle pure quantum systems (n≥3). Here we demonstrate the experimental violation of the above inequalities for W-and GHZ-class of states. We use IBM's five-qubit quantum computer for experimental implementation of these states and illustration of inequalities' violations. Our results clearly show the violations of both Mermin's and Svetlichny's inequalities for W and GHZ states respectively. Being a superconducting qubit-based quantum computer, the platform used here opens up the opportunity to explore multipartite inequalities which is beyond the reach of other existing technologies.

“…IBM quantum experience now plays a significant role in quantum computing community for giving access to two five-qubit and one sixteen-qubit quantum processors named as ibmqx2, ibmqx4 and ibmqx5 respectively. A number of quantum tasks such as quantum algorithms [41,42,43,44,45], quantum error correction code [46,47,48], quantum state and gate teleportation [49,50], quantum information theory [51,52,53,54,55,56,57], quantum simulation [58,59], quantum machine learning [60], quantum artificial intelligence [61], quantum communication devices [62,63,64], have been realized using both five-qubit and sixteen-qubit quantum processors. Here, we consider three qubits, among which one is control and the other two act as the signal qubits.…”

Section: Introductionmentioning

confidence: 99%

Designing quantum router in IBM quantum computer

Reza

Gupta

et al. 2019

Self Cite

Quantum router is an essential ingredient in a quantum network. Here, we propose a new quantum circuit for designing quantum router by using IBM's fivequbit quantum computer. We design an equivalent quantum circuit, by the means of single-qubit and two-qubit quantum gates, which can perform the operation of a quantum router. Here, we show the routing of signal information in two different paths (two signal qubits) which is directed by a control qubit. According to the process of routing, the signal information is found to be in a coherent superposition of two paths. We demonstrate the quantum nature of the router by illustrating the entanglement between the control qubit and the two signal qubits (two paths), and confirm the well preservation of the signal information in either of the two paths after the routing process. We perform quantum state tomography to verify the generation of entanglement and preservation of information. It is found that the experimental results are obtained with good fidelity.Quantum communication is the process of transferring quantum states from one place to another. It plays an important role in the field of quantum information processing [1]. Communication networks are the indispensable technology to transmit quantum information over long distances among the parties connected in a network. Although, classical laws of physics are used for classical communication, it has been predicted that applying the principles of quantum physics and quantum information can enhance the efficiency of communication devices [2,3,4] significantly even if using the similar resources and network architecture [5,6]. Quantum internet has been proposed by Kimble [7], which shows a significant improvement in the area of quantum communication from both the theoretical and experimental aspects. The most notable result has been observed in quantum cryptography [8,9], which can be used for unconditional secure transmission of information. Quantum effects such as arXiv:1803.06530v1 [quant-ph]