Bulletin of the American Physical Society
49th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting
Volume 63, Number 5
Monday–Friday, May 28–June 1 2018; Ft. Lauderdale, Florida
Session R09: Quantum Control and Simulation |
Hide Abstracts |
Sponsoring Units: DQI Chair: Ken Brown, Duke University Room: Grand H |
Thursday, May 31, 2018 10:30AM - 11:00AM |
R09.00001: Deterministic remote entanglement of superconducting circuits through microwave two-photon transitions Invited Speaker: Shyam Shankar Large-scale quantum information processing networks will probably require the entanglement of distant systems that do not interact directly. I will present an experimental realization of such remote entanglement in the superconducting circuit quantum electrodynamics (cQED) platform of quantum information. We have demonstrated deterministic entanglement of two remote superconducting qubits by Raman stimulated emission and absorption of a traveling microwave photon wavepacket. We achieve a Bell state fidelity of 73 \%, well explained by photon losses in the transmission line and decoherence of each qubit. I will then discuss our ongoing efforts to improve the fidelity by entanglement distillation. [Preview Abstract] |
Thursday, May 31, 2018 11:00AM - 11:30AM |
R09.00002: A Universal Analog Quantum Simulator Using Atomic Spins Invited Speaker: Poul Jessen Progress in quantum information science has created a need for experimental platforms that lend themselves to critical evaluation of various paradigms for quantum control and diagnostics. We have developed one such platform using the electron-nuclear spins of individual Cs atoms, forming a 16-dimensional state space that is fully controllable with phase modulated radio-frequency and microwave magnetic fields. Recent work includes the implementation of arbitrary unitary control with state-of-the-art fidelity, and a comparison of optimal strategies for quantum state tomography. The degree of control achievable with this system also allows it to be used as a universal, high-fidelity Analog Quantum Simulator. Broadly defined, an AQS is a controllable quantum system whose time evolution can emulate a Hamiltonian of interest. If used to simulate complex dynamics without error correction such a device becomes vulnerable to exponential loss of precision due to small imperfections. In the classical world this phenomenon manifests itself as deterministic chaos, wherein small perturbations are exponentially amplified over time. Given that imperfections are unavoidable in the real world, this raises the fundamental question whether one can trust the output of an AQS. As a step towards addressing these issues, we are using our AQS to simulate a popular paradigm for quantum chaos, the Quantum Kicked Top, consisting of a periodically driven spin whose classical phase space can be regular, chaotic, or mixed. For our work we pick a spin $J=$15/2, map the 2$J+$1$=$16 spin states onto our AQS, and use optimal control to drive up to a few hundred periods of the QKT dynamics. Our experimental results shed light on several questions of general interest: Is there an optimal map from system to simulator? How accurate must the control be to allow meaningful simulation? And how long can we simulate before the physics of interest (phase space structure, critical points, scrambling, etc.) is compromised by control errors? [Preview Abstract] |
Thursday, May 31, 2018 11:30AM - 12:00PM |
R09.00003: Constructing a multi-module trapped-ion quantum computer prototype Invited Speaker: Winfried K. Hensinger I will discuss progress in constructing a multi-module trapped-ion quantum computer prototype at the University of Sussex. I will provide a short overview of the overall architecture. Previously, it had been proposed to use photonic interconnects to connect individual computer modules. Our new invention introduces connections created by electric fields that allow ions to be transported from one module to another. This architecture also features a method where quantum gates with trapped ions are executed by applying voltages in the presence of a few global rf radiation fields similar in nature to the operation of transistors in a classical computer. I will discuss progress on the construction of the prototype. I will also describe a coherent control method to make quantum gates more resilient to parameter fluctuations and show experimental results. Finally I will discuss a technique to transform existing two-level quantum control methods to new multi-level control methods and provide an application of this method where we map two different qubit types coherently with a fidelity well below the relevant fault-tolerant threshold. [Preview Abstract] |
Thursday, May 31, 2018 12:00PM - 12:30PM |
R09.00004: Engineering Vibrationally Assisted Energy Transfer in a Trapped-Ion Quantum Simulator Invited Speaker: Hartmut Haeffner Many important chemical and biochemical processes in the condensed phase are notoriously difficult to simulate numerically. Often, this difficulty arises from the complexity of simulating dynamics resulting from coupling to structured, mesoscopic baths, for which no separation of time scales exists and statistical treatments fail. A prime example of such a process is vibrationally assisted charge or energy transfer. A quantum simulator, capable of implementing a realistic model of the system of interest, could provide insight into these processes in regimes where numerical treatments fail. We take a first step towards modeling such transfer processes using an ion-trap quantum simulator. By implementing a minimal model, we observe vibrationally assisted energy transport between the electronic states of a donor and an acceptor ion augmented by coupling the donor ion to its vibration. We tune our simulator into several parameter regimes and, in particular, investigate the transfer dynamics in the nonperturbative regime often found in biochemical situations. [Preview Abstract] |
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