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Groundbreaking Progress in Quantum Teleportation: Unprecedented Speed Achieved Over Urban Network
In a remarkable leap forward for quantum teleportation technology, scientists have set a new record for transmission speed, reaching 7.1 qubits per second. This achievement, made possible through cutting-edge innovations, overcomes previous constraints and represents a significant step towards a highly functional and expansive quantum internet.
Quantum teleportation serves as a mechanism for transmitting quantum data to remote sites, facilitated by both quantum entanglement and classical communication channels. Although various quantum light systems have been used to realize this concept—from laboratory settings to real-world trials—the speed of existing systems had not surpassed the Hertz level. This limitation had been a roadblock for the development of a future quantum internet. Notably, using the Micius satellite in low-Earth orbit, scientists had managed to teleport quantum data over 1200 km, albeit at a slower rate.
Improvements in Teleportation Rates
A recent article in Light Science & Application outlines how a research group, headed by Prof. Guangcan Guo and Prof. Qiang Zhou from the University of Electronic Science and Technology of China (UESTC) and in collaboration with Prof. Lixing You from the Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences, achieved the record speed of 7.1 qubits per second. This was accomplished on the UESTC’s “No. 1 Metropolitan Quantum Internet,” establishing a new high in urban-range quantum teleportation.
a. A topographical representation reveals that the network’s switch room houses Alice ‘A’, while Bob ‘B’ and Charlie ‘C’ are based in two distinct labs. All connecting fibers are part of the UESTC network infrastructure. During the test, signals were exclusively transmitted through these specialized fibers, generated by Alice, Bob, and Charlie.
b. The system design involves Alice sending the initial state via a weak coherent single-photon source to Charlie through a quantum channel. Bob’s entanglement source creates entangled photon pairs, with the idler photon sent to Charlie via a different quantum channel. Following a joint Bell-state measurement (BSM) by Charlie, a classical channel sends the BSM outcome to Bob, who applies a unitary transformation to recover the initial state.
Prof. Qiang Zhou, the paper’s corresponding author, stated, “Executing high-speed quantum teleportation outside laboratory confines presents numerous obstacles. This study illustrates the solutions to these challenges and sets a critical benchmark for the future of quantum internet.” A key experimental issue in an operational quantum teleportation setup is conducting effective Bell-state measurements (BSM).
To ensure successful teleportation and enhance BSM efficiency, it is crucial for the photons from Alice and Bob to be identical when they reach Charlie, even after travelling long distances in fiber. The researchers devised a real-time feedback mechanism that quickly stabilized both the path length difference and the polarization of the photons.
Novel Methods and Instrumentation
To produce entangled photons, the team employed a fiber-pigtailed periodically poled lithium niobate waveguide. This led to the creation of a high-quality entangled light source with a repetition rate of 500 MHz for the teleportation system.
The research group, led by Prof. Lixing You and in cooperation with Photon Technology Co., LTD, utilized state-of-the-art superconducting nanowire single-photon detectors. These detectors contributed to achieving high-efficiency BSM and quantum state analysis due to their high sensitivity and negligible noise.
Future Outlook and Applications
Both quantum state tomography and decoy-state techniques were used to ascertain the teleportation fidelities, which significantly surpassed the classical limit of 66.7%. This validates the accomplishment of high-speed urban-range quantum teleportation.
The “No. 1 Metropolitan Quantum Internet of UESTC” aims to build a high-speed, high-fidelity, multi-user, long-distance quantum internet by incorporating integrated quantum light sources, quantum repeaters, and quantum information nodes. The researchers also anticipate that this will expedite the real-world implementation of quantum internet.
The research was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, the Innovation Program for Quantum Science and Technology, and the Sichuan Science and Technology Program.
Reference: “Hertz-rate metropolitan quantum teleportation” by Si Shen et al., 10 May 2023, Light: Science & Applications.
DOI: 10.1038/s41377-023-01158-7
Frequently Asked Questions (FAQs) about Quantum Teleportation
What is the significance of the new speed record in quantum teleportation?
The new speed record of 7.1 qubits per second represents a major advancement in quantum teleportation technology. This breakthrough overcomes previous limitations and sets the stage for a highly functional and far-reaching quantum internet.
Who led the research for this quantum teleportation breakthrough?
The research was led by Prof. Guangcan Guo and Prof. Qiang Zhou from the University of Electronic Science and Technology of China (UESTC), in collaboration with Prof. Lixing You from the Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences.
What challenges were overcome in this experiment?
The main experimental challenge was performing effective Bell-state measurements (BSM). To overcome this, a real-time feedback system was developed to quickly stabilize the path length difference and polarization of the photons from Alice and Bob when they reach Charlie.
What technology was used to achieve this feat?
Innovative technology was employed, including a fiber-pigtailed periodically poled lithium niobate waveguide to produce entangled photons and state-of-the-art superconducting nanowire single-photon detectors for high-efficiency BSM and quantum state analysis.
What are the potential applications of this breakthrough?
The achievement holds promise for the development of a high-speed, high-fidelity, multi-user, long-distance quantum internet. It is expected to further practical applications of quantum internet by combining integrated quantum light sources, quantum repeaters, and quantum information nodes.
How was the research funded?
The study received financial support from the National Key Research and Development Program of China, the National Natural Science Foundation of China, the Innovation Program for Quantum Science and Technology, and the Sichuan Science and Technology Program.
What methods were used to validate the results?
Both quantum state tomography and decoy-state techniques were employed to calculate the teleportation fidelities. These fidelities were found to be well above the classical limit of 66.7%, confirming the accomplishment of high-speed metropolitan quantum teleportation.
What is the “No. 1 Metropolitan Quantum Internet of UESTC”?
The “No. 1 Metropolitan Quantum Internet of UESTC” is the platform on which the record-breaking teleportation speed was achieved. It aims to develop a robust quantum internet infrastructure featuring high speed, high fidelity, multiple users, and long distances.
What does the term “qubit” mean?
A qubit, or “quantum bit,” is the basic unit of quantum information. Unlike classical bits, which can be either 0 or 1, qubits can exist in a superposition of states, allowing for more complex and faster computations.
What are the future implications of this research?
The breakthrough is expected to expedite the development and practical application of quantum internet. It serves as a critical milestone and provides a technological foundation upon which future advancements in quantum telecommunications can be built.
More about Quantum Teleportation
- Quantum Teleportation: An Overview
- Understanding Quantum Entanglement
- The University of Electronic Science and Technology of China (UESTC)
- Shanghai Institute of Microsystem and Information Technology
- Bell-State Measurement Explained
- National Key Research and Development Program of China
- National Natural Science Foundation of China
- DOI for the Original Study
7 comments
Holy smokes, the future is here folks! Can’t believe they cracked the Bell-state measurement issue. Prof. Qiang Zhou and his team are like the avengers of quantum science.
With advancements like this, we need to start thinking about the policy implications. Who regulates a quantum internet? What are the cybersecurity concerns?
The implications are mind-blowing. High-speed, long-distance quantum internet could revolutionize how we do… well, everything. Can’t wait to see what’s next.
Single piece of fiber-pigtailed periodically poled lithium niobate waveguide… Try sayin that three times fast lol. But seriously, the tech here is next level.
Interesting, but let’s not forget this is still largely experimental. When will we see actual applications? Money’s bein poured into this but what’s the ROI?
Look at the funding sources, National Key Research and China’s Natural Science Foundation? Clearly China’s takin quantum research seriously. Western nations better catch up fast.
Wow, 7.1 qubits per second? That’s insane! So were finally moving past the lab experiments and gettin real world results. This is big.