Bulletin of the American Physical Society
APS March Meeting 2022
Volume 67, Number 3
Monday–Friday, March 14–18, 2022; Chicago
Session A35: Multi-party and Long Distance Quantum NetworksFocus Recordings Available
|
Hide Abstracts |
Sponsoring Units: DQI Chair: Filip Rozp?dek, DQI Room: McCormick Place W-193B |
Monday, March 14, 2022 8:00AM - 8:36AM |
A35.00001: Distributed entanglement and teleportation on a multi-node quantum network Invited Speaker: Sophie Hermans A future quantum internet can unlock fundamentally new technologies by sharing entangled states and quantum information across the nodes of the network. In the past decade, many buildings blocks of such a network have been demonstrated. In particular, the heralded distribution of entanglement between two physically separated nodes and quantum teleportation has been achieved on various platforms, however connecting multiple nodes into a multi-node quantum network remained an open challenge. |
Monday, March 14, 2022 8:36AM - 8:48AM |
A35.00002: Illinois Express Quantum Network for Distributing and Controlling Entanglement on Metro-Scale Prem Kumar, Jordan M Thomas, Gregory S Kanter, Ely M Eastman, Wenji Wu, Joaquin F Chung Miranda, Nikolai Lauk, Venkata R Valivarthi, Cristian Pena, Neil Sinclair, Si Xie, Rajkumar Kettimuthu, Panagiotis Spentzouris, Maria Spiropulu The Illinois Express Quantum Network (IEQNET) is a program for developing metro-scale quantum networking over deployed optical fiber infrastructure. While new technologies, such as quantum repeaters, will be needed to realize the long-term goals of quantum networking, IEQNET focuses on leveraging currently available technology (with provision for future upgrades as technology develops). Two of the prime needs in quantum information systems are distributing entanglement and using entanglement to perform quantum state teleportation. These needs should be met while simultaneously allowing higher-power classical signals to share the same fiber, both for the purposes of enabling communications to support quantum applications and for independent coexistence of high data-rate classical channels. We will summarize the main elements of the IEQNET architecture, that leverages software-defined-networking (SDN) technology to perform traditional wavelength routing and assignment between the Q-nodes, as well as the status of its implementation at the three sites of the project in the Chicago metropolitan area. We will also show coexistence of quantum entangled and classical light over deployed optical fiber at the sites. Wavelength engineering/filtering allows milliwatts copropagating power with quantum light from a photon-pair source with broad entangled spectrum. |
Monday, March 14, 2022 8:48AM - 9:00AM |
A35.00003: QUANT-NET : a novel quantum internet testbed Venkata R Valivarthi DOE's quantum internet blueprint envisions milestones that include intercampus entanglement distribution and interstate quantum entanglement distribution using quantum repeaters. QUANTNET, a novel quantum internet testbed is designed to make key strides towards these milestones by not only demonstrating the basic functions of the quantum internet, but also evaluating candidate technologies and protocols for scaling the network. In particular, the testbed aims to demonstrate a three-node trapped-ion network with two stations at LBNL and one processor at UCB allowing for gate teleportation, quantum repeater protocols, and distributed quantum computing. |
Monday, March 14, 2022 9:00AM - 9:12AM |
A35.00004: A Deployed Quantum Local Area Network with Flex-Grid Technology Muneer Alshowkan, Brian P Williams, Philip G Evans, Nageswara Rao, Emma M Simmerman, Hsuan-Hao Lu, Navin B Lingaraju, Andrew M Weiner, Claire E Marvinney, Yun-Yi Pai, Benjamin J Lawrie, Nicholas A Peters, Joseph M Lukens The development of quantum communications networks is crucial for advancing quantum information science, including the highly anticipated Quantum Internet. Nevertheless, quantum network testbeds have so far not fully utilized modern lightwave communications technologies, such as flexible-grid bandwidth distribution. Here we summarize recent work [M. Alshowkan et al., PRX Quantum 2, 040304 (2021)] demonstrating flex-grid entanglement distribution in a quantum local area network (QLAN), connecting nodes in three campus buildings that are time-synchronized by the Global Positioning System (GPS). The network enables both adaptive bandwidth provisioning and simultaneous distributed remote detection with off-the-shelf control systems. We use log-negativity to measure the quality of the distributed polarization entanglement, which provides a general metric of link performance in terms of entangled bits per second. After demonstrating successful entanglement distribution for two allocations of our eight dynamically reconfigurable channels, we realize the first deployed fiber network demonstration of remote state preparation (RSP). Our results highlight an advanced paradigm for managing entanglement resources in quantum networks of ever-increasing complexity and service demands. |
Monday, March 14, 2022 9:12AM - 9:24AM Withdrawn |
A35.00005: Abstract Withdrawn
|
Monday, March 14, 2022 9:24AM - 9:36AM |
A35.00006: Simulations of Quantum Networks on High-Performance Computers Alexander Kolar, Xiaoliang Wu, Joaquin F Chung Miranda, Dong Jin, Rajkumar Kettimuthu, Martin Suchara Simulation has emerged as a useful tool for quantum network performance evaluations, protocol design, and experiment planning. However, the need to explore a large parameter space and perform simulations at the individual photon level lead to prohibitively long execution times. To reduce the execution time while retaining simulation accuracy, we introduce new parallel simulation techniques that provide better scalability for large networks. We address the unique challenges with parallel simulation of quantum networks, such as the need to track entanglement across the network. We develop the first parallel discrete event simulator (PDES) of quantum networks by extending the SeQUeNCe quantum network simulator. We describe our PDES quantum simulator design, including a centralized manager of quantum states, offloading of work to processes, and process synchronization optimization. Finally, we also quantify the benefits of PDES on simulation scalability by simulating several large-scale quantum networks, including linear networks, caveman graph topologies, and Internet autonomous system (AS) networks of various sizes. |
Monday, March 14, 2022 9:36AM - 9:48AM |
A35.00007: Developing Practical Quantum Network Protocols Martin Suchara, Rajkumar Kettimuthu, Hong Qiao, James Williams, Tian Zhong We outline a vision for developing the Quantum Internet Protocol and describe our experiences with implementing a protocol prototype that allows transmission and synchronization of time-bin encoded photons. Ideally, quantum network protocols should satisfy a long list of requirements, including the ability to transmit heterogeneous types of quantum and classical information; ensure precise timing; scale with the number of users and applications; and allow upgradability. We work towards these goals by introducing a new protocol that allows transmission of DV, CV, and hybrid entanglement and uses in-band transmission of classical control signals. We also report on our development and experimental demonstration of a protocol prototype that uses FPGAs to control the transmission and synchronization of time-bin encoded photons between a pair of network nodes separated by 20 km of optical fiber [1]. Our technique achieved timing synchronization with picosecond accuracy and required only a single dedicated optical fiber and standard internet connection between the two network nodes. The accurate timing information allowed us to use time-bin encoding and increase data transmission speeds. |
Monday, March 14, 2022 9:48AM - 10:00AM |
A35.00008: Photon-Efficient Energy-Time Entanglement QKD Using Spatially-Coupled Irregular-Repeat-Accumulate Error Correction Codes Murat C Sarihan, Siyi Yang, Kai-Chi chang, Shyam Venkatasubramanian, Lara Dolecek, Chee Wei Wong High-dimensional quantum key distribution (QKD) protocols based on energy-time entangled photons are unique thanks to their high bits per photon efficiency, due to infinite Hilbert space. However, for demanding QKD channels, pumping the entanglement source higher to increase raw key rate inevitably leads to a larger fraction of uniformly distributed errors, originating from an increased background and multi-photon emissions, which necessitates robust ECC schemes. Previous QKD error correction studies utilize widespread multi-level-coding (MLC) low-density parity-check coding, which is binary by design and independently corrects each bit layer. In this work, we developed non-binary spatially-coupled (SC) irregular repeat accumulate (IRA) codes that we strategically combine two advanced low-density-parity-check (LDPC) codes, the SC codes and the IRA codes. These SC-IRA codes are tailored for the energy-time entangled QKD channels through the proposed optimization framework. Our simulation results show that SC-IRA codes can reach up to 20.62% higher photon efficiency than the MLC scheme. We will utilize our Mbit/s level high-alphabet time-bin encoding testbed to demonstrate SC-IRA advantage up to 10-bits encoding. |
Monday, March 14, 2022 10:00AM - 10:12AM |
A35.00009: Quantum-Enabled Communication without a Phase Reference Quntao Zhuang A phase reference has been a standard requirement in continuous-variable quantum sensing and communication protocols. However, maintaining a phase reference is challenging due to environmental fluctuations, preventing quantum phenomena such as entanglement and coherence from being utilized in many scenarios. We show that quantum communication and entanglement-assisted communication without a phase reference are possible, when a short-time memory effect is present. The degradation in the communication rate of classical or quantum information transmission decreases inversely with the correlation time. Exact solutions of the quantum capacity and entanglement-assisted classical and quantum capacity for pure dephasing channels are derived, where non-Gaussian multipartite-entangled states show strict advantages over usual Gaussian sources. For thermal-loss dephasing channels, lower bounds of the capacities are derived. The lower bounds also extend to scenarios with fading effects in the channel. In addition, for entanglement-assisted communication, the lower bounds can be achieved by a simple phase-encoding scheme on two-mode squeezed vacuum sources, when the noise is large. |
Monday, March 14, 2022 10:12AM - 10:24AM |
A35.00010: Intrinsic Non-Locality and Device-Independent Conference Key Agreement Aby Philip, Eneet Kaur, Peter Bierhorst, Mark M Wilde Conference key agreement is a multipartite protocol that can be executed using genuinely multipartite entangled resources. Several questions remain unanswered with regards to device-independent conference key agreement rates. In this work, we introduce the multipartite intrinsic non-locality as a resource quantifier for the multipartite scenario of device-independent conference key agreement. We prove that this quantity is additive, convex, and monotone under a class of free operations called local operations and common randomness. As one of our technical contributions, we establish a chain rule for multipartite mutual information, which may be of independent interest. We then use this chain rule to establish the multipartite intrinsic non-locality as an upper bound on secret key rate in the general multipartite scenario of DI conference key agreement. We discuss various examples of DI conference key protocols and compare our upper bounds for these protocols with known lower bounds. Upper bounds on recent experimental realizations of device-independent quantum key distributions are also calculated. |
Monday, March 14, 2022 10:24AM - 10:36AM |
A35.00011: Multipartite Entanglement Distribution using a Central Quantum-Network Node Guus Avis, Filip D Rozpedek, Stephanie Wehner We study the performance (rate and fidelity) of distributing multipartite entangled states in a quantum network through the use of a central node. Specifically, we consider the scenario where the multipartite entangled state is first prepared locally at a central node, and then transmitted to the end nodes of the network through quantum teleportation. As our first result, we present leading-order analytical expressions and lower bounds for both the rate and fidelity at which a specific class of multipartite entangled states, namely Greenberger-Horne-Zeilinger (GHZ) states, are distributed. Our analytical expressions for the fidelity accurately account for time-dependent noise encountered by individual quantum bits while stored in quantum memory. As our second result, we provide a comparison to an alternative scenario where the central node is unable to locally prepare GHZ states. Apart from these two results, we outline how the teleportation-based scheme could be physically implemented using ion traps or NV centers in diamond. |
Monday, March 14, 2022 10:36AM - 10:48AM |
A35.00012: Experimental demonstration of entanglement delivery using a quantum network link layer Matteo Pompili, Carlo Delle Donne, Ingmar te Raa, Bart van der Vecht, Guilherme Ferreira, Lisa de Kluijver, Arian Stolk, Sophie Hermans, Wojciech Kozlowski, Przemysław Pawełczak, Stephanie Wehner, Ronald Hanson By sharing entangled states over global distances, the future Quantum Internet will unlock new possibilities in secure communication, distributed quantum computation and metrology. Fundamental primitives for entanglement-based quantum networks have been demonstrated on several physical platforms. However, it remains an outstanding challenge moving past physics experiments and delivering entanglement as a service. |
Monday, March 14, 2022 10:48AM - 11:00AM |
A35.00013: Perspectives of microwave quantum key distribution Florian Fesquet, Kirill G Fedorov, Fabian Kronowetter, Michael U Renger, Qi-Ming Chen, Kedar Honasoge, Yuki Nojiri, Oscar Gargiulo, Achim Marx, Frank Deppe, Rudolf Gross One of the cornerstones of quantum communication is an unconditionally secure distribution of classical keys between remote parties. This can be achieved by exploiting quantum features of electromagnetic waves, such as entanglement or superposition. However, these quantum properties are known to be susceptible to noise and losses, which are essential for free-space communication scenarios. In this work, we theoretically investigate perspectives of continuous-variable free-space quantum key distribution (QKD) at microwave frequencies. Using a protocol based on displaced squeezed states, our model predicts that continuous-variable microwave quantum key distribution with propagating microwaves can be unconditionally secure at room temperatures up to distances of around 200 meters and even outperform conventional QKD protocols at telecom wavelengths under realistic weather conditions. Furthermore, we conduct experimental studies on microwave QKD with propagating microwave squeezed states. The latter are generated and manipulated by using superconducting Josephson parametric amplifiers. We demonstrate the experimental feasibility of unconditional security for microwave QKD in cryogenic enviroments and project these results to near-term open-air applications. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700