Bulletin of the American Physical Society
APS March Meeting 2021
Volume 66, Number 1
Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA
Session P32: Noisy Intermediate Scale Quantum Computers VLive
|
Hide Abstracts |
Sponsoring Units: DQI DCOMP Chair: James Medford, Northrop Grumman - Mission Systems |
Wednesday, March 17, 2021 3:00PM - 3:12PM Live |
P32.00001: Analyzing the Performance of Variational Quantum Factoring on a Superconducting Quantum Processor Amir Karamlou, William Simon, Travis Scholten, Amara Katabarwa, Borja Peropadre, Yudong Cao Quantum computers hold promise as accelerators for certain classically-intractable problems – necessitating a hybrid quantum-classical system. Understanding how these two computing paradigms work in tandem is necessary to identify where hybrid systems could provide an advantage. In the context of quantum optimization, we study such systems and investigate the tradeoff between quantum resources, such as circuit depth, and solution accuracy. We use the variational quantum factoring (VQF) algorithm as a prototypical hybrid workflow and execute experimental demonstrations using a superconducting quantum processor. We factor 1,099,551,473,989 (3 qubits), 3,127 (4 qubits), and 6,557 (5 qubits) with up to 8 layers of the QAOA ansatz and analyze the success probability at each layer. Our results demonstrate how the success probability trends with the number of layers and reveal that coherent noise is a dominant source of error affecting the algorithm's performance. This suggests that VQF could form an “application benchmark" to measure the performance of quantum computers. |
Wednesday, March 17, 2021 3:12PM - 3:24PM Live |
P32.00002: Confinement and Entanglement Dynamicson a Digital Quantum Computer Joseph Vovrosh, Johannes Knolle Confinement describes the phenomenon when the attraction between two particles grows with their distance, most prominently found in quantum chromodynamics (QCD) between quarks. In condensed matter physics, confinement can appear in quantum spin chains, for example, in the one dimensional transverse field Ising model (TFIM) with an additional longitudinal field, famously observed in the quantum material cobalt niobate or in optical lattices. Here, we establish that state-of-the-art quantum computers have reached quantum simulation capabilities to explore confinement physics in spin chains. We report quantitative confinement signatures of the TFIM on an IBM quantum computer observed via two distinct velocities for information propagation from domain walls and their mesonic bound states. We also find the confinement induced slow down of entanglement spreading by implementing randomized measurement protocols for the second order Renyi entanglement entropy. Our results are a crucial step for probing non-perturbative interacting quantum phenomena on digital quantum computers beyond the capabilities of classical hardware. |
Wednesday, March 17, 2021 3:24PM - 3:36PM Live |
P32.00003: Analogue Floquet quantum simulation on NISQ devices Daniel Malz, Adam Smith Previous theoretical and experimental research has shown that current NISQ devices constitute powerful platforms for analogue (continuous-time) quantum simulation. Indeed, it is known that a lattice of superconducting qubits naturally implements a Bose-Hubbard model. With the exquisite level of control offered by state-of-the-art quantum computers, we show that one can go further and implement a wide class of Floquet Hamiltonians, or time-dependent Hamiltonians in general. We then implement a single-qubit version of these models in the IBM Quantum Experience and experimentally realize a temporal version of the Bernevig-Hughes-Chang Chern insulator. From our data we can infer the presence of a topological transition, thus realizing an earlier proposal of topological frequency conversion by Martin, Refael, and Halperin. |
Wednesday, March 17, 2021 3:36PM - 3:48PM Live |
P32.00004: Holographic quantum dynamics simulations on a trapped ion quantum computer Eli Chertkov, Michael Foss-Feig, David Hayes, Andrew C Potter One of the most promising applications for a quantum computer is simulating the dynamics of strongly interacting quantum systems, a task that is hard to perform on a classical computer and yet important for studying processes such as chemical reactions and quantum information scrambling. Mid-circuit measurement and qubit re-use (MCMR) are powerful tools, available in Honeywell's trapped ion quantum charge-coupled device architecture [1], that can allow quantum computers to better utilize their limited resources. The holographic quantum dynamics algorithm (holoQUADS) developed in Ref. [2] uses MCMR to simulate the time-evolution of an infinitely-long correlated state, i.e., a matrix product state, using only a finite number of qubits. In this talk, we present our results for holoQUADS simulations performed on a Honeywell quantum computer for "dual-unitary" circuits, a class of quantum circuits whose time evolution is exactly solvable [3], and find good agreement with theoretical predictions. |
Wednesday, March 17, 2021 3:48PM - 4:00PM Live |
P32.00005: Quantum computer-aided design: digital quantum simulation of quantum processors Thi Ha Kyaw, Tim Menke, Sukin Sim, Nicolas Sawaya, William Oliver, Gian Giacomo Guerreschi, Alan Aspuru-Guzik With the increasing size of quantum processors, the sub-modules that constitute the processor will become too large to accurately simulate on a classical computer. Therefore, one would soon have to fabricate and test each new design primitive and parameter choice in time-consuming coordination between design, fabrication, and experimental validation. To circumvent this slow-down, we address the question of how one can design and test the performance of the sub-modules of next-generation quantum devices--by using existing quantum computers. We show how the energy spectra of transmons can be obtained by variational hybrid quantum-classical algorithms that are well-suited for near-term noisy quantum computers. We also numerically demonstrate how single-and two-qubit gates can be realized via Suzuki-Trotter decomposition for digital quantum simulation. Our methods pave a new way towards designing candidate quantum processors when the demands of calculating sub-module properties exceed the capabilities of classical computing resources. |
Wednesday, March 17, 2021 4:00PM - 4:12PM Live |
P32.00006: A Dynamically Reconfigurable Quantum Processor Architecture Brian Marinelli, Jie Luo, Kyunghoon Lee, David Ivan Santiago, Irfan Siddiqi Despite recent improvements in two-qubit gate fidelities in superconducting qubit architectures, the entangling of distant qubits still requires cascading multiple nearest neighbor two-qubit gates, so the overall compound error rate grows exponentially with the distance between the qubits on the connectivity graph. We seek to combine the controllability of superconducting quantum circuits with the flexibility of the all-to-all qubit connectivity graphs experimentally demonstrated in AMO experiments. Here we propose our scheme to utilize 3D integration techniques and parametric coupling in building a high-performance 3D QPU with programmable arbitrary qubit connectivity enabled by the chip architecture. Our scheme employs a squid tunable multimode bus resonator coupled to all of the qubits to enable the parametric coupling. By using a single chip scale bus resonator to couple all qubits we transfer the reconfigurability complexity to the room temperature electronics where multiplexed microwave signals control the qubit connectivity graph. |
Wednesday, March 17, 2021 4:12PM - 4:24PM Live |
P32.00007: Operating a Dynamically reconfigurable Quantum Processor with 8 Superconducting Transmon Qubits Jie Luo, Brian Marinelli, Kyunghoon Lee, David Ivan Santiago, Irfan Siddiqi
|
Wednesday, March 17, 2021 4:24PM - 4:36PM Live |
P32.00008: Performance Study of Superconducting Quantum Computing Chips under Different Architecture Design Wei Hu, Jiawei Pi, Weiye Xia, Xinding Zhang, Hua Xu Quantum Computing (QC) has attracted rapidly growing interest of the researchers in the last few decades because of its vast potential applications and superb computing power. Currently various physical QC systems are under study, and existing and near-term quantum computers have reached dozens to hundreds of qubits. It has been widely agreed that the computing capacity of a quantum chip is determined by many factors, such as qubit quantity, qubit quality, gating fidelity, and processor architecture. However, it is still lack of systematically study of these factors, especially at different connectivity and geometry. We designed a representative design architecture set of QC chips with different qubit connectivity and geometry. And run a benchmark quantum circuit set and collected the performance indicators on different QC chips. We analyzed the performance of circuit with different connectivity quantitatively, and found that the quantum processor qubit connectivity and geometry, can have a huge impact on the performance of the quantum algorithms. This work provides QC researchers a systematic approach to evaluate their processor design, and moreover, to optimize their processor design. |
Wednesday, March 17, 2021 4:36PM - 4:48PM Live |
P32.00009: Toffoli Gate Depth Reduction in Fixed Frequency Transmon Qutrits Alexey Galda, Michael Cubeddu, Naoki Kanazawa, Prineha Narang, Nathan D Earnest Quantum computation is conventionally performed using binary quantum logic by operating on quantum bits, or qubits. However, most quantum devices naturally have multiple accessible energy levels beyond the lowest two traditionally used to define a qubit. While unintentional occupation of these higher energy states introduces computational errors, intentional use of these states can provide benefits that are potentially useful in the noisy quantum compute era. We present how, using Qiskit Pulse, one can program a quantum computer over the cloud at the pulse level and implement ternary logic operations on fixed-frequency transmons. From this, we realize a three-qubit Toffoli gate using two different decompositions with 50% fewer (3 instead of 6) two-transmon gates, when compared with the usual binary implementation using CNOT gates.We discuss the theoretical requirements for such qutrit decompositions and our experimental progress of implementing them on pulse-control-enabled devices made available by IBM Quantum. We highlight the advantages and disadvantages of using higher-energy states to obtain optimized circuits, compared to default qubit realizations. Our work encourages an investigation of cloud-based quantum circuit optimization techniques using multi-level quantum systems. |
Wednesday, March 17, 2021 4:48PM - 5:00PM Live |
P32.00010: Reliability of analog quantum simulation in chaotic systems Karthik Chinni, Pablo Poggi, Ivan Deutsch NISQ era is characterized by the absence of fully fault-tolerant quantum simulators, which raises a question about the reliability of such devices. We thus seek to assess the reliability of an analog quantum simulator, which does not have access to error correction, in the presence of chaotic perturbations. We do this by studying the fundamental properties of the many-body systems such as the ground state and the dynamical quantum phase transitions in the Lipkin-Meshkov-Glick (LMG)model. First, we show that the presence of a small time-dependent perturbation can render the system chaotic. We then show that the critical point estimates of these phase transitions, obtained from the quantum simulation of its dynamics, are robust to the presence of this chaotic perturbation, even though other aspects of the system are fragile and therefore cannot be reliably extracted from this simulator. |
Wednesday, March 17, 2021 5:00PM - 5:12PM Live |
P32.00011: Using Inherent Qubit Decoherence To Simulate Thermal Relaxation in Spin Chemistry Systems on NISQ Machines Brian Rost, Barbara A Jones, Mariya Vyushkova Current and near-term quantum computers (i.e. NISQ devices) are limited in their computational power in part due to qubit decoherence. Here we seek to take advantage of qubit decoherence as a resource for simulating the behavior of real-world quantum systems, which are always subject to decoherence, with no additional computational overhead. We show how to use the natural qubit decoherence to accurately simulate experimental results of quantum beats in radical ion pairs undergoing thermal relaxation on a quantum computer. We further implement our method to simulate two interesting chemical systems that are run on a quantum computer made available by IBM Quantum, and compare against directly implementing the decoherence channels using ancilla qubits. Using error mitigation techniques, we are able to achieve very good agreement with both theoretical and experimental data. |
Wednesday, March 17, 2021 5:12PM - 5:24PM Live |
P32.00012: Pipeline architecture for a silicon qubit processor Sofia Patomäki, Michael A. Fogarty, Zhenyu Cai, Simon Charles Benjamin, John J. L. Morton Noisy intermediate-scale quantum (NISQ) devices seek quantum speedup over classical systems without full quantum error correction. We propose a NISQ processor architecture using a qubit pipeline in which all run-time control is applied globally, simplifying the number and complexity of required control and interconnect resources. This is achieved by progressing qubit states through a layered physical array of structures which realise single- and two-qubit gates. Such approach lends itself to NISQ applications such as variational quantum eigensolvers requiring repetitions of the same calculations, or small variations thereof. In exchange for simplified run-time control, a larger number of physical structures is required for shuttling the qubits as the circuit depth now corresponds to a physical axis of grid structures. However, qubit states can be pipelined through the arrays densely for repeated runs to make more efficient use of physical resources. This architecture is well suited to silicon quantum dot electron spin qubits due to their high density and scalability. We demonstrate how the key elements of single- and two-qubit gates and qubit state shuttling can be implemented in the silicon spin-qubit platform for the qubit pipeline. |
Wednesday, March 17, 2021 5:24PM - 5:36PM Live |
P32.00013: A survey of dynamical decoupling sequences on a programmable superconducting quantum computer Nic Ezzell, Bibek Pokharel, Daniel Lidar Dynamical decoupling (DD) is the judicious placement of control pulses to decouple a quantum system from its environment without the need for feedback. Error-suppression through DD sequences is well suited for noisy intermediate-scale quantum (NISQ) era quantum computers (QCs) due to its low resource overhead. In this work we update the status of previous DD surveys in light of recent advancements with cloud-based superconducting qubit devices. In particular, we use an IBM cloud QC with additional control of input pulses through the OpenPulse API. These additional controls allow us to implement certain robust and non-uniformly spaced sequences which--to our knowledge--have not been tested on cloud-based QCs. We use our experimental results to (1) find the best performing DD sequence and (2) test predictions from DD theory. For example, we address the effect of finite-pulse width errors, concatenation depth, and delay duration between pulses on DD performance. |
Wednesday, March 17, 2021 5:36PM - 5:48PM Live |
P32.00014: Mid-circuit measurement and active feed-forward in the Honeywell QCCD quantum computer Ciaran Ryan-Anderson Mid-circuit measurement and active feed-forward are essential ingredients to fault-tolerant quantum error correction, and the QCCD architecture naturally lends itself to these operational primitives. Ion-transport operations allow for individual qubits to be spatially isolated, where they may be safely interrogated and reinitialized with focused laser beams without damaging idling qubits. Here we present experimental characterizations of these operations including both primitive as well as algorithmic benchmarking results. We will also discuss our results’ implications for the QCCD architecture’s capabilities. |
Wednesday, March 17, 2021 5:48PM - 6:00PM Not Participating |
P32.00015: Realization of higher winding number topological states of the long-range magnonic SSH model using superconducting circuits Adrian Tan, Jie Luo, Brian Marinelli, David Ivan Santiago, Irfan Siddiqi, Austin Minnich Superconducting circuits are emerging as a promising platform to probe topological phenomena that are difficult to observe in real materials. The Su-Schrieffer-Heeger (SSH) model is the paradigmatic example of a Hamiltonian exhibiting nontrivial topological invariants and topological insulator states. While the topological states of the magnonic SSH model have been realized in superconducting platforms, the topological phases of the extended SSH model with long-range interactions have not been reported on any experimental platform. Here, we report the realization of topological states of the extended magnonic SSH model using an analog superconducting circuit quantum simulator with all-to-all connections. We measure the winding number of the topological phases and probe the topological edge states by introducing single-qubit excitations. Our results paves the way to realize other exotic topological phases using superconducting circuits. |
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