Upcoming Events
Fall 2024 Seminar Series:
“Exploring Selective Radiance with Trapped Atoms on a Nanophotonic Resonator” with Chen-Lung Hung – Purdue University
“New Platforms for Quantum Sensing and Quantum Computing” with Nathalie de Leon – Princeton University
Paolo Cappellaro – Massachusetts Institute of Technology
Michael Krueger – Israel Institute of Technology
Cindy Regal – University of Colorado Boulder
Sinéad M. Griffin – Berkeley Lab
Kater Murch – Washington University in St. Louis
Artur Izmaylov – University of Toronto
Exploring Selective Radiance With Trapped Atoms on a Nanophotonic Resonator
Chen-Lung Hung, Associate Professor of Physics and Astronomy at Purdue University
September 12, 11:00 am – noon
West Hall, Room 411
Abstract:
Control and manipulation of the collective radiative states of atomic systems could bring new opportunities for quantum many-body physics and quantum networks. In this talk, I will discuss our recent investigation on “selective radiance,” a phenomenon in which an atomic excitation couples to a specific photonic channel with collective enhancement (called ‘superradiance’) but to all other channels with suppression (‘subradiance’). Following our recent experimental realization of cold atom trapping on a nanophotonic microring resonator, we study how a dense atomic ensemble collectively couples to a whispering-gallery-mode in the resonator and to other free space modes. I will discuss the decay dynamics of an atomic ensemble following long and short excitation pulses, with the former driving the system into a steady state and the latter into a so-called timed-Dicke state. I will discuss the potential of our platform to realize selective radiance in an atom array and explore collective quantum optics with trapped atoms coupled to nanophotonic circuits.
Bio:
Dr. Hung received his PhD in Physics at the University of Chicago in 2011, where he developed an in-situ microscopy technique on two-dimensional atomic quantum gases to study quantum phase transitions. Before joining Purdue in 2015 as a faculty member, he held a postdoctoral fellowship at the California Institute of Technology and developed one of the first photonic crystal atom-photon interfaces for quantum optics. His research directions at Purdue University span from studying out-of-equilibrium many-body physics using atomic quantum gases to interfacing ultracold atoms with nanophotonic circuits for quantum optics and many-body physics with photon-mediated long-range interactions. He is a recipient of the AFOSR Young Investigator Award and the NSF CAREER award.
New Platforms for Quantum Sensing and Quantum Computing
Nathalie de Leon, Associate Professor of Electrical and Computer Engineering at Princeton University
September 26, 11:00 am – noon
Michigan Memorial Phoenix Project (2000PML)
Abstract:
The nitrogen vacancy (NV) center in diamond exhibits spin-dependent fluorescence and long spin coherence times under ambient conditions, enabling applications in quantum information processing and sensing. NV centers near the surface can have strong interactions with external materials and spins, enabling new forms of nanoscale spectroscopy. However, NV spin coherence degrades within 100 nanometers of the surface, suggesting that diamond surfaces are plagued with ubiquitous defects. I will describe our recent efforts to correlate direct materials characterization with single spin measurements to devise methods to stabilize highly coherent NV centers within nanometers of the surface. We deploy these coherent shallow NV centers for a new nanoscale sensing technique, whereby we use covariance measurements of two or more NV centers to measure two-point magnetic field correlators.
Our approach for correlating surface spectroscopy techniques with single qubit measurements to realize directed improvements is generally applicable to many systems. Separately, I will describe our recent efforts to tackle noise and microwave losses in superconducting qubits. Building large, useful quantum systems based on transmon qubits will require significant improvements in qubit relaxation and coherence times, which are orders of magnitude shorter than limits imposed by bulk properties of the constituent materials. This indicates that loss likely originates from uncontrolled surfaces, interfaces, and contaminants. Previous efforts to improve qubit lifetimes have focused primarily on designs that minimize contributions from surfaces. However, significant improvements in the lifetime of planar transmon qubits have remained elusive for several years. We have recently fabricated planar transmon qubits that have both lifetimes and coherence times exceeding 0.3 milliseconds by using tantalum as the material in the capacitor. Following this discovery, we have parametrized the remaining sources of loss in state-of-the-art devices using systematic measurements of the dependence of loss on temperature, power, and geometry. This parametrization, complemented by direct materials characterization, allows for rational, directed improvement of superconducting qubits.
Bio:
Nathalie de Leon is an associate professor of Electrical and Computer Engineering at Princeton, where she focuses on quantum sensing with NV centers in diamond, quantum networks with solid state defect systems and nanophotonics, and new material platforms for superconducting qubits. She received her BS from Stanford University in 2004 and PhD from Harvard University in 2011. She then worked as a CIQM and Element Six postdoctoral fellow at Harvard. Nathalie joined the faculty of Princeton University as an assistant professor in Electrical and Computer Engineering in 2016, where she was later promoted to associate professor. Her group works at the interface of quantum optics, atomic physics, condensed matter and device physics, materials science, surface spectroscopy, nanofabrication, and spin physics to uncover sources of noise and loss in quantum systems, and uses these insights to design new quantum platforms. She is currently the materials thrust leader of the Co-design Center for Quantum Advantage, a DOE National Quantum Information Science Center, and she was elected as Vice Chair of the APS Division of Quantum Information in 2024. Nathalie received the Air Force Office for Scientific Research Young Investigator Award in 2016, the Sloan Research Fellowship in Physics in 2017, the NSF CAREER Award in 2018, the DARPA Young Faculty Award in 2018, and the DOE Early Career Award in 2018, the Gordon and Betty Moore Foundation Experimental Physics Investigator Award in 2023, and the APS Rolf Landauer and Charles H. Bennett Award in Quantum Computing in 2023.
Paolo Cappellaro, Professor of Nuclear Science and Engineering, Professor of Physics at Massachusetts Institute of Technology
October 10, 11:00 am – noon
West Hall, Room 411
Michael Krueger, Assistant Professor / Senior Lecturer
Department of Physics and Solid State Institute
Technion at Israel Institute of Technology
October 17, 11:00 am – noon
West Hall, Room 411
Cindy Regal, Professor, Baur-SPIE Endowed Chair in Optical Physics and Photonics at University of Colorado Boulder
October 24, 11:00 am – noon
Michigan Memorial Phoenix Project (2000PML)
Sinéad M. Griffin, Staff Scientist at the Berkeley Lab
November 7, 11:00 am – noon
West Hall, Room 411
Kater Murch, Professor of Physics at Washington University in St. Louis
November 21, 11:00 am – noon
Michigan Memorial Phoenix Project (2000PML)
Artur Izmaylov, Professor of Chemistry at the University of Toronto
December 5, 11:00 am – noon
West Hall, Room 411
Past Events
Winter 2024 Seminar Series
Opportunities and Challenges for Diamond in Quantum Applications
Shannon Nicley, Assistant Professor in the Department of Electrical and Computer Engineering at Michigan State University (MSU)
April 18, 11:00 am – noon
East Room (1st floor) of Pierpont Commons
Zoom option
Diamond is a highly attractive material as a solid-state host for a class of crystal defect spin-based qubits, which exhibit high stability even under ambient conditions. Carbon-12 isotopically purified diamond is also spin free, allowing for exceptionally long coherence times. I will introduce the challenges and opportunities in this field and present the results of our ongoing efforts to identify new defects in diamond with long coherence times and high-quality optical interfaces, as well as our efforts to controllably create vacancy defects in solid state systems through multiphoton femtosecond laser nanofabrication.
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Engineering of atomic and solid-state quantum emitters for sensing
Jennifer Choy, Assistant Professor at the Department of Electrical and Computer Engineering at UW–Madison April 4, 11:00 am – noon
The Michigan League
Henderson Room (3rd floor)
Zoom option
I will describe the realization of quantum sensors based on two material platforms: alkali atoms such as rubidium, and spin defects in diamond. These platforms have complementary properties that make each uniquely advantageous for certain sensing applications, as well as challenges that currently limit their sensing performance and functionality. I will discuss engineering approaches to miniaturize and improve the performance of quantum sensors, including photonic-integration of atomic magnetometers, improving light-matter interactions with solid-state spin defects, and stabilization of near-surface quantum emitters through surface treatments.
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Demonstration of Algorithmic Quantum Speedup
Daniel Lidar, Viterbi Professor of Engineering at USC
March 21, 11:00 am – noon
Pierpont Commons
Boulevard Room (1st floor)
Zoom option
Despite the development of increasingly capable quantum computers, an experimental demonstration of an algorithmic quantum speedup employing today’s non-fault-tolerant devices has remained elusive. In this talk, I will report on three very recent demonstrations of such a speedup, focusing on how solution times scale with problem size. Two of the demonstrations use IBM’s superconducting quantum computers and involve modified versions of foundational black-box quantum algorithms. In contrast with recent quantum supremacy demonstrations, these quantum speedups do not rely on complexity-theoretic conjectures. The third demonstration uses a D-Wave quantum annealer and involves approximate optimization in the context of spin glass problems. In all cases, our work incorporates tailored quantum error suppression methods, which we found to be necessary in order for the quantum speedup to appear.
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Quantum Optical Interconnects
Marko Lončar, Harvard’s School of Engineering and Applied Sciences (SEAS)
Michigan League
Henderson Room (3rd floor)
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Building a Quantum World with Trapped Ions
Norbert Linke, Assistant Professor of Physics at the Duke Quantum Center (DQC)
This talk will describe the development of an atomic physics experiment into a quantum computer and quantum simulator. Our system is based on a chain of 171Yb+ ions with individual laser beam addressing. This fully connected device can be configured to run any sequence of single- and two-qubit gates, making it in effect an arbitrarily programmable quantum computer. The high degree of control can be used for digital quantum circuits, but also for analog and hybrid quantum simulations, including quantum-classical optimization routines. We operate this machine in user-facility mode, working with many external collaborators and growing its capabilities with every new application. I will present recent results from a lattice gauge theory simulation. Finally, I will describe our effort towards networking ion trap quantum computers in a city-sized network for new quantum technology applications.
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Quantum photonics with rare-earth atoms in solids
Dr. Elizabeth Goldschmidt, Assistant Professor of Physics at the University of Illinois Urbana-Champaign.
February 8, 11 am – 12 pm
Henderson Room (3rd floor) at the Michigan League
Zoom option
Optically active and highly coherent emitters in solids are a promising platform for a wide variety of quantum information applications, particularly quantum memory and other quantum networking tasks. Rare-earth atoms, in addition to having record long coherence times, have the added benefit that they can be hosted in a wide range of solid-state materials. We can thus target particular materials (and choose particular rare-earth species and isotopes) that enable certain application-specific functionalities. I will give an overview of this promising field and discuss several ongoing projects with rare-earth atoms in different host materials and configurations. This includes efforts to identify and grow new materials with rare-earth atoms at stoichiometric concentrations in order to reduce disorder-induced inhomogeneous broadening, as well as photonic integration of rare-earth doped samples to increase the light-atom interaction for practical quantum devices.
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Nanoscale electron paramagnetic resonance and quantum opto-mechanics with diamond spin qubits
January 25, 11 am
Pierpont Commons, Boulevard Room (1st Floor Mazznine)
Gurudev Dutt, Associate Professor at the University of Pittsburgh, will be presenting “Nanoscale electron paramagnetic resonance and quantum opto-mechanics with diamond spin qubits” as part of the Quantum Research Institute’s winter seminar series. A Zoom option is also provided.
Seminar Description:
Single spins associated with nitrogen-vacancy (NV) defects in diamond have emerged as a promising and versatile experimental platform for quantum information processing. They can be used as nodes in optically connected quantum networks, as sensors for magnetic imaging with sub-micron resolution, for detecting and engineering quantum states of nano-mechanical oscillators, and even as probes in biological systems. Our group has demonstrated improvements to dynamic range and sensitivity of magnetometry using phase estimation algorithms, and carried out electron paramagnetic resonance detection and spectroscopy of single Cu ions on the diamond surface. I will also discuss a unique system in our lab where we magnetically trap and laser cool diamond microcrystals under high-vacuum room-temperature conditions for the first time, and discuss the path forward to observing quantum superpositions of macroscopically separated motional states.
Fall 2023 Seminar Series
Quantum-enhanced interferometric imaging: A step toward quantum-enhanced very-long-baseline interferometry for astronomy – 11/30/23
Dr. Brian Smith, Professor of Physics at the University of Oregon, will be presenting “Quantum-enhanced interferometric imaging: A step toward quantum-enhanced very-long-baseline interferometry for astronomy” as part of the Quantum Research Institute’s fall seminar series from 11am – noon in the Hussey Room (2nd floor) at the Michigan League on Thursday, November 30th. A Zoom option is also provided.
Seminar Description:
We report a laboratory demonstration of interferometric imaging using a path-entangled single-photon state as a reference field distributed to spatially separated receivers to measure the spatial distribution of an extended incoherent source. The use of distributed entanglement between the receiving stations in this protocol allows measurements without requiring direct interference of the collected light and provides a route to larger baseline separations that could enhance the precision of astronomical telescopes.
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Phononic Bath Engineering of a Superconducting Qubit – 11/16/23
Dr. Johannes Pollanen, Associate Professor in the department of Physics and Astronomy at Michigan State University, will be presenting “Phononic Bath Engineering of a Superconducting Qubit” as part of the Quantum Research Institute’s fall seminar series from 11am – noon in the Boulevard Room (1st mezzanine floor) at Pierpont Commons on Thursday, November 16th. A Zoom option is also provided.
Seminar Description:
Interactions between a quantum system and its environment typically lead to unwanted decoherence and dissipation. However, if the environmental degrees of freedom can be sufficiently well understood, or even engineered, dissipation can be harnessed for the preparation and manipulation of such open quantum systems. In this talk I will discuss our recent results investigating a novel open quantum system composed of a superconducting transmon qubit coupled to surface piezophonon devices. In this hybrid quantum system we are able to engineer dissipation in the form of tailor-made phononic loss to control quantum information states of the qubit.
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Emerging Materials for Quantum Technologies – 11/2/2023
Dr. Yong P. Chen, Karl Lark-Horovitz Professor of Physics and Astronomy at Purdue and Director of the Purdue Quantum Science and Engineering Institute, will be presenting “Emerging Materials for Quantum Technologies” as part of the Quantum Research Institute’s fall seminar series from 11am – noon in the Kalamazoo Room (2nd floor) at the Michigan League on Thursday, November 2nd. A Zoom option is also provided.
Seminar Description:
This seminar will discuss some emerging materials — particularly in the space of 2D/layered and topological materials ranging from 2D semiconductors to topological insulators — and their promising properties and potential uses in quantum technologies.
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Quantum Research Institute seminar on 10/19: Linran Fan
The third event in the Quantum Research Institute’s Fall 2023 seminar series will be from Dr. Linran Fan, Assistant Professor in the Chandra Family Department of Electrical and Computer Engineering at The University of Texas at Austin.
Dr. Fan’s talk, titled “Hybrid Integrated Photonics for Quantum Information Processing” will take place on Thursday, Oct 19th from 11am – noon in the Boulevard Room (1st floor mezzanine) at Pierpont Commons. A Zoom option is also provided.
Photonics will play a central role in future quantum technology, offering the unique and indispensable capability to conserve quantum coherence over long distances and inter-connect different quantum systems. This talk will present our efforts in developing hybrid integrated photonic platforms, which enable the exploration of new quantum phenomena, the development of novel quantum information functions, and the improvement of quantum device performance.
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Quantum Research Institute seminar on 10/5: Amit Agrawal
The second event in the Quantum Research Institute’s Fall 2023 seminar series will be from Dr. Amit Agrawal, project leader of the Ultrafast Nano-Optics Group within the Physical Measurement Laboratory at the National Institute of Standards and Technology.
Dr. Agrawal’s talk, titled ” Integrated Optical Control of Atomic Quantum Systems” will take place on Thursday, Oct 5th from 11am – noon in the Kalamazoo Room (2nd floor) at the Michigan League. A Zoom option is also provided.
Seminar Description:
Optical control of quantum matter – from trapped atoms and ions to quantum dots and defects, is foundational for quantum information science and technology. Development of integrated photonics opens the possibility for realization of scalable circuits with complex functionalities, advancing both science and technology frontiers and enabling real-world applications in quantum sensing and precision measurements. Here, we present our work on scalable, robust and multifunctional nanophotonic interfaces to trap neutral atoms or address trapped ions. Our nanophotonic platform, replacing bulk optical elements, promises increased complexity and functionality in a batch-fabricated optical microsystem ultimately fully replacing the laboratory optical table to enable cold atom clocks and quantum computers.
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Co-Designed Quantum Error Correction: Liang Jian – 9/21/23
Dr. Jiang’s talk, titled “Co-Designed Quantum Error Correction” will take place on Thursday, Sept 21st from 11am – noon in the Boulevard Room (1st floor) at Pierpont Commons (North Campus). A Zoom option is also provided.
Seminar Description:
Our goal is to design quantum error correction schemes that suppress hardware-specific errors while meeting diverse application needs. This presentation covers the design of error-correcting codes that effectively handle practical errors, including custom schemes for AMO and solid-state platforms, as well as applications in quantum computing, communication, and sensing.
Contact Us
Email the Quantum Research Institute: [email protected]