Format results
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Talk
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QuEra - quantum computing with neutral atoms:
Anna Knorr Perimeter Institute
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Gibbs Sampling of Periodic Potentials on a Quantum Computer
Arsalan Motamedi University of Waterloo
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Representing quantum states with spiking neural networks
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Stefanie Czischek University of Ottawa
- Stefanie Czischek
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Quantum hypernetworks
Juan Carrasquilla Vector Institute for Artificial Intelligence
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A Study of Neural Network Field Theories
Anindita Maiti Northeastern University
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Self-Correcting Quantum Many-Body Control using Reinforcement Learning with Tensor Networks
Friederike Metz Okinawa Institute of Science and Technology Graduate University
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Matchgate Shadows for Fermionic Quantum Simulation
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Kianna Wan Stanford University
- Kianna Wan
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Quantum state control of ultracold chemistry
Alan Jamison Institute for Quantum Computing (IQC)
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Photon-bubble turbulence in cold atomic gases
Hugo Terças Instituto de Plasmas e Fusão Nuclear
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Rydberg atoms in Bose-Einstein condensed environments: cold bubble chambers and mesoscopic entanglement
Sebastian Wüster Indian Institute of Science Education and Research, Bhopal
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Towards an optogalvanic flux sensor for nitric oxide based on Rydberg excitations
Harald Kübler University of Stuttgart
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Opportunities and Limitations for Warm Rydberg Electric Field Sensors
Paul Kunz United States Army Research Laboratory
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Advances in Sensitivity and Pulse Detection with Rydberg-Atom Electrometry
Stephanie Bohaichuk Quantum Valley Ideas Laboratories
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Coherent Light Shift of Alkaline-Earth Rydberg Atoms
Patrick Cheinet Laboratoire Aimé Cotton, CNRS
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Time-optimal gates for quantum computing with Rydberg atoms
Guido Pupillo University of Strasbourg
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Quantum circuits on neutral atom computers
Mark Saffman University of Wisconsin–Madison
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Exploring quantum spin models with tunable arrays of Rydberg atoms
Daniel Barredo Institut d'Optique-CNRS & CINN-CSIC
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New Frontiers in Machine Learning and Quantum
This workshop will bring together a group of young trendsetters working at the frontier of machine learning and quantum information. The workshop will feature two days of talks, and ample time for participants to interact and form new collaborations in the inspiring environment of the Perimeter Institute. Topics will include machine learning, quantum field theory, quantum information, and unifying theoretical concepts.
Territorial Land AcknowledgementPerimeter Institute acknowledges that it is situated on the traditional territory of the Anishinaabe, Haudenosaunee, and Neutral peoples.
Perimeter Institute is located on the Haldimand Tract. After the American Revolution, the tract was granted by the British to the Six Nations of the Grand River and the Mississaugas of the Credit First Nation as compensation for their role in the war and for the loss of their traditional lands in upstate New York. Of the 950,000 acres granted to the Haudenosaunee, less than 5 percent remains Six Nations land. Only 6,100 acres remain Mississaugas of the Credit land.
We thank the Anishinaabe, Haudenosaunee, and Neutral peoples for hosting us on their land.
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Quantum state control of ultracold chemistry
Alan Jamison Institute for Quantum Computing (IQC)
The advent of ultracold molecules opens the possibility to explore chemical reactions with perfect control of the quantum states of the reactants. We report on several surprising results of our work with ultracold NaLi molecules. First, we demonstrate a factor of 100 control of reaction rates between NaLi molecules and Na atoms by changing the atom's spin state. This ability to slow reactions allowed us to demonstrate sympathetic cooling of molecules for the first time. Next, we explore two very different collisional resonances. A resonance in NaLi+Na reactions exemplifies the standard description of chemical resonances. The other, for NaLi+NaLi, is the first ultracold molecule-molecule resonance observed and runs completely counter to the standard description. Simple models relate the complex chemical dynamics to the simple physics of a Fabry-Perot resonantor and point a number of open questions in chemical dynamics that can be explored with ultracold molecules. -
Photon-bubble turbulence in cold atomic gases
Hugo Terças Instituto de Plasmas e Fusão Nuclear
Turbulent radiation flow is ubiquitous in many physical systems where light–matter interaction becomes relevant. Photon bubble instabilities, in particular, have been identified as a possible source of turbulent radiation transport in astrophysical objects such as massive stars and black hole accretion disks. Here, we report on the experimental observation of a photon bubble instability in cold atomic gases, in the presence of multiple scattering of light. A two-fluid theory is developed to model the coupled atom–photon gas and to describe both the saturation of the instability in the regime of quasi-static bubbles and the low-frequency turbulent phase associated with the growth and collapse of photon bubbles inside the atomic sample. We also employ statistical dimensionality reduction techniques to describe the low-dimensional nature of the turbulent regime. The experimental results reported here, along with the theoretical model we have developed, may shed light on analogue photon bubble instabilities in astrophysical scenarios. Our findings are consistent with recent analyses based on spatially resolved pump–probe measurements. -
Rydberg atoms in Bose-Einstein condensed environments: cold bubble chambers and mesoscopic entanglement
Sebastian Wüster Indian Institute of Science Education and Research, Bhopal
"S. Tiwari, S. Rammohan, A. Mishra, A. Pendse, A. K. Chauhan, R. Nath, F. Engel, M. Wagner, R.Schmidt, F. Meinert, A. Eisfeld and S. Wüster Indian Institute of Science Education and Research, Bhopal India Palacký University, Olomouc, Czech Republic Indian Institute of Science Education and Research, Pune, India Max Planck Institute for the Physics of Complex Systems, Dresden, Germany Universität Stuttgart, Germany Max-Planck-Institute of Quantum Optics and MCQST, Garching, Germany Rydberg Atoms in highly excited electronic states with n=30-200 can be excited within BoseEinstein condensates (BECs), and while lifetimes are shorter than in vacuum [1,2], they live long enough to cause a response of the BEC mean field [3]. During this, thousands of ground-state atoms are present within the Rydberg orbit, allowing the study of atoms moving within atoms [4]. We present beyond-mean field models of the joint Rydberg-BEC dynamics, showing how either can be used to probe the other. For multiple Rydberg atoms in a single electronic state, we show that the phase coherence of thecondensate allows the tracking of mobile Rydberg impurities akin to the function of bubblechambers in particle physics [5]. For a single Rydberg atom with multiple electronic states, weprovide spectral densities of the BEC as a decohering environment [6], and show that the BECcan image a signature of the entangling evolution that causes Rydberg q-bit decoherence [7] or serve as non-Markovian environment for quantum simulations. [1] Schlagmüller et al. PRX 6 (2016) 031020. [2] Kanungo et al. PRA 102 (2020) 063317. [3] Balewski et al. Nature 502 (2013) 664. [4] Tiwari et al. arXiv:2111.05031 (2021) [5] Tiwari et al. PRA 99 (2019) 043616. [6] Rammohan et al. PRA 103 (2021) 063307. [7] Rammohan et al. PRA(Letters) 104 (2021) L060202." -
Measurements of blackbody-radiation-induced transition rates between high-lying S, P, and D Rydberg levels
Donatella Ciampini Università di Pisa
We report experimental measurements of the rates of blackbody-radiation-induced transitions between highlying (n > 60) S, P, and D Rydberg levels of rubidium atoms in a magneto-optical trap using a hybrid field ionization and state-selective depumping technique. Our results reveal significant deviations of the measured transition rates from theory for well-defined ranges of the principal quantum number. We assume that the most likely cause for those deviations is a modified blackbody spectrum inside the glass cell in which the magneto-optical trap is formed, and we test this assumption by installing electrodes to create an additional microwave cavity around the cell. From the results, we conclude that it should be possible to use such external cavities to control and suppress the blackbody-radiation-induced transitions." -
Towards an optogalvanic flux sensor for nitric oxide based on Rydberg excitations
Harald Kübler University of Stuttgart
I will talk about the applicability of a new kind of gas sensor based on Rydberg excitations. From a gas mixture the molecule in question is excited to a Rydberg state. By succeeding collisions with all other gas components this molecule ionizes and the emerging electrons can be measured as a current. I will show Doppler-free spectra for the A <- X transition, an estimate of the excitation efficiency dependent on the used laser powers, the applied charge-extraction voltage as well as the overall gas pressure and a first Stark map of NO Rydberg states recorded with cw excitation. -
Opportunities and Limitations for Warm Rydberg Electric Field Sensors
Paul Kunz United States Army Research Laboratory
Electric field sensors based on warm vapors of Rydberg atoms have distinguishing features that offer new application possibilities. A single sensor can operate over a wide spectrum of frequencies, from DC to THz, with a consistent instantaneous baseband bandwidth of approximately 10MHz. The sensor head containing the vapor is highly transparent and can be made small relative to the electric field wavelengths, enabling accurate measurements with sub-wavelength spatial resolution. Presently Rydberg sensors rely on the spectroscopic method of electromagnetically induced transparency (EIT) for preparing and probing the atoms, and though simple and effective, this places limits on the sensitivity and instantaneous bandwidth of the sensor. I will discuss these limitations and the optimal EIT parameter regime considering presently available laser technology, and show performance of a promising new prototype vertical external cavity surface emitting laser (VECSEL). Finally, I will present results on recent demonstrations, such as a Rydberg-based spectrum analyzer with sensitivity of -145dBm/Hz and dynamic range >80 dB. -
Advances in Sensitivity and Pulse Detection with Rydberg-Atom Electrometry
Stephanie Bohaichuk Quantum Valley Ideas Laboratories
The strong interaction of optically excited Rydberg atoms with external fields has made them promising for the detection of radio frequency (RF) electric fields with high sensitivity. Such Rydberg-atom based sensors offer advantages over conventional metal antennas in RF transparency and self-calibration, enabled by all-dielectric construction and extremely well-known atomic properties. In this talk, we describe recent advances in the sensing of low amplitude RF electric fields and the timing of sub-microsecond RF pulses using room temperature Cesium vapour cells. We examine their transient response to RF pulses with durations ranging from 10 μs to 50 ns, identifying the dependence of atomic time scales on Rabi frequencies and dephasing mechanisms. We present a method for extracting the arrival time of RF pulses in a typical two-photon setup using a matched filter tailored to the atomic response, achieving a field sensitivity down to ~240 nV cm-1 Hz-1/2 and a timing precision of ~30 ns. On the other hand, practical operation at room temperature results in the self-calibration and sensitivity of this setup being limited by residual Doppler broadening. We therefore develop a novel sub-Doppler approach using a colinear three-photon scheme, which extends the self-calibrated Autler-Townes regime to significantly weaker RF electric fields. With this setup, we achieve a ~200 kHz spectral linewidth of the Rydberg atoms’ electromagnetically induced transparency within a room temperature vapour cell. The results demonstrate the potential of Rydberg atombased sensors for use in test and measurement, communications, and radar applications. " -
Coherent Light Shift of Alkaline-Earth Rydberg Atoms
Patrick Cheinet Laboratoire Aimé Cotton, CNRS
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Time-optimal gates for quantum computing with Rydberg atoms
Guido Pupillo University of Strasbourg
"Neutral atoms have emerged as a competitive platform for digital quantum simulations and computing. In this talk, we discuss recent results on the design of time-optimal two- and three-qubit gates for neutral atoms, where entangling gates are implemented via the strong and long-range interactions provided by highly excited Rydberg states. We combine numerical and semi-analytical quantum optimal control techniques to obtain theoretically laser pulses that are “smooth”, time-optimal and “global” -- that is, they do not require individual addressability of the atoms. This technique improves upon current implementations of the controlled-Z (CZ) and the three-qubit C2Z gates with just a limited set of variational parameters, demonstrating the potential of quantum optimal control techniques for advancing quantum computing with Rydberg atoms." -
Quantum circuits on neutral atom computers
Mark Saffman University of Wisconsin–Madison
"Neutral atom quantum computers with Rydberg mediated entangling gates are rapidly advancing as a leading platform for quantum information processing. I will present recent results running quantum algorithms for preparation of multi-qubit GHZ states, phase estimation, and hybrid quantum/classical optimization. Future fault tolerant quantum processors will require large numbers of qubits, high fidelity gates, and error correcting protocols. Work in progress towards fault tolerance including preparation of arrays of more than 1000 atoms, mid-circuit measurements, and multi-qubit gates will be presented" -
Exploring quantum spin models with tunable arrays of Rydberg atoms
Daniel Barredo Institut d'Optique-CNRS & CINN-CSIC
"Rydberg atoms in arrays of optical tweezers offer a new perspective for the quantum simulation of many body systems. In this talk, I will give a brief overview about this platform and describe our efforts to control Rydberg interactions to explore different types of Hamiltonians. Through recent experimental results, I will illustrate the implementation of the Ising [1] and XXZ [2] Hamiltonians to study quantum magnetism. Finally, I will show our first steps to scale up the atom numbers in our platform by using a cryogenic environment [3]. References: [1] P. Scholl et al., Nature 595, 233 (2021). [2] P. Scholl et al., PRX Quantum 3, 020303 (2022). [3] K.N. Schymik et al., Phys. Rev. Applied 16, 034013 (2021)."