Quantum Information Science for Fundamental Physics

US/Mountain
Aspen Center for Physics
Aaron Chou (Fermilab), Brian Swingle (University of Maryland, College Park), Kathryn Zurek, Konrad Lehnert (University of Colorado and NIST)
Description

The last decade has seen wonderful progress on fundamental physics, including both the discovery of the Higgs boson by the LHC and the direct detection of gravitational waves and black holes by LIGO. These successes increasingly highlight other fundamental challenges in physics ranging from understanding the nature of dark matter to unraveling the quantum physics of spacetime itself. At the same time, there have been dramatic improvements in our ability to manipulate complex quantum systems and a concomitant explosion in our theoretical understanding of the nature of information in a quantum universe. An exciting possibility raised by these two parallel developments is that quantum information and systems could provide a powerful new approach to questions in fundamental physics. Nevertheless, efforts in this direction are still nascent. 

One set of ideas revolves around using engineered quantum systems to make ultra-precise measurements to directly detect faint dark matter signatures. Another set of ideas attempts to decode the way spacetime emerges from microscopic degrees of freedom using the language of entanglement, complexity, and computation. Given these and other early developments, the time is ripe for a meeting across communities to share ideas and look forward.  This Aspen Winter Conference will bring these communities together in a focused meeting to identify common goals and look for new opportunities. Such a meeting should be more productive than previously possible thanks to the new common language of quantum information and a new set of experimental tools of broad interest.

The application deadline is November 30, 2019.  

Please complete your application at https://aspenphys.org/physicists/winter/winterapps.html

 

 

    • 17:00
      Reception and registration at the Aspen Center for Physics
    • Morning session: Big questions
      • 1
        Perspectives on Quantum Information Science for Fundamental Physics
        Speaker: John Preskill (Caltech)
      • 2
        Quantum electromagnetic sensors and the search for axion dark matter below 1 micro-eV
        Speaker: Kent Irwin (Stanford University)
      • 09:20
        Coffee break
      • 3
        New Ideas in Dark Matter Detection
        Speaker: Kathryn Zurek
      • 4
        Quantum technologies for gravitational wave detectors
        Speaker: Nergis Mavalvala (MIT)
    • Evening session: Quantum information and space-time
      • 5
        Comments on QI in accelerating cosmology (phenomenological and thought-experimental)
        Speaker: Eva Silverstein (Stanford)
      • 6
        Quantum entropy generated by dynamical evolution

        We introduce the notion of a time density matrix which captures a probabilistic ensemble of systems in specified states at different times. The quantum entropy of a time density matrix quantifies the information needed to track the unitary evolution of an arbitrary quantum system. As such it can grow with time, and is a finer probe of the dynamics of the system than the quantum entropy of a regular density matrix. This dynamical quantum entropy is expected to be useful in characterizing chaotic quantum systems, as well as in studying how certain quantum systems are encoded in dual gravity theories.

        Speaker: Josephine Suh
    • Poster session: Posters
    • Morning session: Quantum sensing and error correction
      • 7
        Sensing, Entanglement, and Scrambling

        We will begin by discussing optimal entanglement-based protocols for measuring spatially varying fields with a sensor network. We will then discuss fast protocols for preparing the required entangled states and lower bounds on the preparation time. Finally, we will discuss applications of these and related bounds to quantum information scrambling.

        Speaker: Alexey Gorshkov
      • 8
        Advanced Characterization and Sensing with Squeezed Optomechanical Systems

        In this talk I will outline quantum-enhanced sensing modalities for nanoscale displacement and phase
        sensing. Optomechanical devices use optical readout of micro/nano-electromechanical systems (MEMS)
        displacement in order to transduce displacement and phase signals. New detection modes that focus on
        ultrasonic measurements have brought the shot noise of the optical field into play when transducing
        signals near resonance, allowing for shot noise limited measurements even at room temperature.
        However, state of the art approaches to date have been unable to leverage the lower noise floor away
        from the mechanical resonance frequency because minimum resolvable signals fall below the noise floor
        off-resonance. As a result, many MEMS measurement techniques can only probe the RF responses of
        materials or fields at discrete mechanical frequencies, with slow measurements associated with
        micromechanical ringdown times that are highly susceptible to nonlinear dynamics. In the shot noise
        limited regime, far below the back-action limit, these devices are good candidates for quantum sensing,
        where quantum effects like entanglement are used to enhance the readout of optical beam
        displacements, revealing signals that were previously buried in the noise. For example, in the case of
        atomic force microscopy, the ability to lower the noise floor beyond current classical limits enables
        broadband materials characterization critical to describing electronic dynamics in complex materials
        with orders of magnitude faster acquisition times than are currently available. I will compare and
        contrast two common readout techniques, with added quantum enhancement: direct detection readout
        and interferometric readout. I will outline a new scheme that relies on squeezed light and nonlinear
        interferometry to move nanoscale displacement sensing, phase sensing, and quantum imaging below
        the shot noise limit.

        Speaker: Raphael Pooser (Oak Ridge National Laboratory)
      • 09:00
        Coffee break
      • 9
        Cavity Optomechanics: Generating Mechanical Interference Fringes and Brillouin Optomechanical Strong Coupling

        Cavity quantum optomechanics utilizes electromagnetic fields to generate and study quantum states of motion of macroscopic mechanical oscillators. The field has undergone significant growth recently owing to its significant promise for both quantum technology development and to test the foundations of physics. Our new team at Imperial College London - the Quantum Measurement Lab - pursue a combination of experiment and theory in these directions with key interests including quantum-state engineering of mechanical systems and exploring the quantum-to-classical transition. In this talk, results from two of our research programs will be presented. Firstly, our work towards creating a mechanical superposition state will be described including experimentally generating interference fringes in the motion of a mechanical oscillator using single-photon detection [1], and theoretical work proposing how to grow a mechanical superposition state using a sequence of pulsed interactions and single-photon measurements [2]. Secondly, our experimental work on Brillouin optomechanics with high-frequency phonons (~10 GHz) will be presented including the first observation of Brillouin optomechanical strong coupling [3]. This observation provides a powerful new direction that unites several favorable properties for mechanical quantum state engineering including very low optical loss and absorption, and back-scatter operation to allow the signal to be easily separated from the pump.

        [1] Ringbauer et al, New J. Phys. 20, 053042 (2018).
        [2] Clarke and Vanner, Quantum Sci. Technol. 4, 014003 (2019).
        [3] Enzian et al, Optica 6, 7 (2019).
        https://groups.physics.ox.ac.uk/QMLab/

        Speaker: Michael Vanner (Imperial College, London)
      • 10
        Quantum Control of Harmonic Oscillator Motional States of Ions

        This talk will give an overview of recent work on quantum control of the har- monic oscillator states of motion realized with trapped ions at NIST. We prepare non-classical states of the motion of a single Be+ or Mg+ ion, such as approxi- mately pure number states of ion motion up to n = 100 [1], coherent superpo- sitions of the ground state with number states up to n = 16 [1] and squeezing to more than 20 dB over a motional ground state [2]. These states are useful to characterize ion motional excitation and frequency noise over a wide range of time-scales, with a quantum advantage over more traditional approaches.

        Besides being useful for exploring quantum control of harmonic oscillators, atomic ions are also sensitive to coherent electric fields, such as those that may result from hidden photons or from axions in the presence of a magnetic field. The motional frequencies of ions in the quantum regime typically range from 100 kHz - 10 MHz and can be tuned by changing their confining potential. Harmonic oscillator quality factors of at least 105 have been observed and even better quality factors may be realized by more careful elimination of noise and drifts in the system. Therefore, it could be interesting to use ions as field-sensors for searches of axions and hidden photons in a frequency range where electrical circuits may be limited by thermal noise. Similar experiments can also be done in a Penning trap with hundreds of ions [3]. Penning trap operation requires a strong magnetic field that can potentially serve to convert axion fields into elec- tric fields and the larger number of ions allows for faster averaging of projection noise during readout of the ion state.

        [1] K. C. McCormick, J. Keller, S. C. Burd, David J. Wineland, A. C. Wilson,
        and D. Leibfried, Nature 572, 86 (2019).

        [2] S. C. Burd, R. Srinivas, J. J. Bollinger, A. C. Wilson, D. J. Wineland, D.
        Leibfried, D. H. Slichter, and D. T. C. Allcock, Science 364, 1163 (2019).

        [3] K. A. Gilmore, J. G. Bohnet, B. C. Sawyer, J. W. Britton, and J. J.
        Bollinger, Phys. Rev. Lett. 118, 263602 (2017).

        This work was supported by the NIST Quantum Information Program.

        Speaker: Dietrich Leibfried
    • Public Event at Aspen Center for Physics: Physics Cafe
    • Public Event at Aspen Center for Physics: Public lecture from John Preskill
      • 11
        Quantum Computing and the Entanglement Frontier
        Speaker: John Preskill (Caltech)
    • Morning session: Quantum information and black holes
      • 12
        Replica Wormholes and the Black Hole Interior

        Naïve semiclassical arguments suggest that the entropy of Hawking radiation should continue to grow even at very late times, a result that is inconsistent with the unitarity of quantum mechanics. In this talk, I will argue that a more careful replica trick calculation shows that the gravitational path integral becomes dominated (at late times) by saddles containing spacetime wormholes. These wormholes cause the entropy to decrease after the Page time, consistent with unitarity, and allow information to escape from the interior of the black hole.

        Speaker: Geoff Penington (Stanford University)
      • 13
        A Traversable Wormhole Teleportation Protocol in the SYK Model
        Speaker: Ping Gao
    • 09:00
      Coffee break
    • Morning session: New technologies
    • Evening session: Dark matter detection ideas
      • 16
        Axion and Gravitational Waves from Black Hole Superradiance

        Theories beyond the Standard Model of particle physics often predict new, light, feebly interacting particles whose discovery requires novel search strategies. A light particle, the QCD axion, elegantly solves the outstanding strong-CP problem of the Standard Model; cousins of the QCD axion can also appear, and are natural dark matter candidates. I will show how rotating black holes turn into axionic and gravitational wave beacons, creating nature's laboratories for ultralight bosons. When an axion's Compton wavelength is comparable to a black hole size, energy and angular momentum from the black hole source exponentially-growing bound states of particles, forming gravitational atoms'. Thesegravitational atoms' emit monochromatic gravitational wave signals, enabling gravitational wave observatories to discover ultralight axions. If the axions interact with one another, instead of gravitational waves, black holes populate the universe with axion waves.

        Speaker: Masha Baryakhtar (NYU)
      • 17
        Searching for Dark Matter with Athermal Phonon Detectors Throughout the Mass Range from 50meV through 500MeV

        Substantial astronomical observations have established that approximately 25% of the energy density of the universe is composed of cold non-baryonic dark matter, whose detection and characterization could be key to improving our understanding of the laws of physics. Over the past three decades, physicists have largely focused on searching for dark matter within the 10 GeV-1 TeV range (WIMPs), unfortunately without success. These experimental failures and recent theoretical realizations, have motivated new experimental searches for dark matter with much lower masses.

        In this talk, we’ll discuss the experimental requirements when searching for dark matter throughout the mass range from 50meV- 500 MeV. We’ll also discuss recent R&D breakthroughs in athermal phonon sensor technology that will enable experiments that are being proposed using silicon, polar crystal and superfluid He as the detector material.

        Speaker: Matt Pyle (Berkeley)
      • 18
        ABRACADABRA-10cm: Searching for Axions and Preparing for DMRadio-m3
        Speaker: Lindley Winslow (MIT)
      • 18:00
        Coffee break
      • 19
        Dark Matter Detection with Magnons and Phonons
        Speaker: K. Zhang
      • 20
        Plasmons and Excesses in Low-Threshold Dark Matter Experiments

        Spectacular advances in dark matter detection experiments, using a variety of detector materials, have pushed energy thresholds below 60 eV and charge detection to single-charge resolution. Eleven such low-threshold experiments have observed an unexplained excess of events at low energies. Surprisingly, the excess rates of ~ 10 Hz/kg in semiconductor detectors are the same to within a factor of a few, independent of exposure, overburden, shielding, or detector location, while the rates at noble liquid detectors are much smaller but are also consistent to within an order of magnitude. Taken together, I will argue that these disparate results can be explained if some external source is exciting a plasmon resonance in the semiconductor detectors, which is absent in disordered materials. If the external source happens to be dark matter, the couplings and masses required to explain the observed rate are consistent with standard thermal mechanisms for obtaining the correct relic abundance. I will mention numerous testable predictions for this scenario, many of which imply interesting new detector physics whether or not dark matter is the source of the observed events.

        Speaker: Yoni Kahn (UIUC)
    • 20:00
      Conference banquet
    • Morning session: Holography and quantum simulation
      • 21
        Synthesis of Quantum-Noise-"Free" Systems

        The sensitivity of quantum-noise limited systems can be greatly increased by engineering the quantum correlations of the probing field either externally (e.g. squeezed light) or internally (e.g. strong nonlinearities and/or coherent quantum control). Techniques used in the optimization of classical electrical circuits can be applied to the maximization of SNR in the context of the quantum Rao-Cramer bound, including losses, and thereby minimize the impact of decoherence on the reconstruction of the desired signal (e.g. LIGO, ADMX, etc). Not only can this approach be used for linear measurements of classical fields, but also for hypothesis testing of deviations from QM and GR.

        Speaker: Rana Adhikari
      • 22
        Mechanical architectures for fundamental physics detection

        Mechanical sensing technologies in the classical and quantum regimes have been demonstrated across an enormous range of frequency and mass scales. I'll overview some ideas about using these sensing techniques to look a diverse variety of dark matter candidates, including ultra-light (m < meV) and ultra-heavy (m > m_GUT) fields. The theory of quantum backaction-evading measurements, especially of the momentum of a device, will play a key role in the more ambitious examples.

        Speaker: Dan Carney
      • 23
        A Supersonically expanding BEC: An expanding universe in the lab

        The massive scale of the universe makes the experimental study of cosmological inflation
        difficult. This has led to an interest in developing analogous systems using table top
        experiments. One possible system for such simulations is an expanding atomic quantum gas.
        In recent experiments, we have modeled the basic features of an expanding universe by
        drawing parallels with an expanding ring-shaped Bose Einstein Condensate (BEC). The Bose-
        Einstein condensate can be thought of as a vacuum for phonons, and used in analogy to the
        quantum field proposed to have driven the expansion of the early universe. Here, while the
        ring-shaped BEC serves as the background vacuum, the phonons are the analogue to photons
        in the expanding universe. We have studied the dynamics of a supersonically expanding ringshaped
        BEC both experimentally and theoretically. I will present our results and discuss
        prospects for future experiments.

        Speaker: Gretchen Campbell
      • 09:30
        Coffee break
      • 24
        Quantum Gravity in the Lab

        The trend of theoretical advances in AdS/CFT suggests that quantum gravity is broadly applicable as an effective description of chaotic many-body physics. Experimental realizations of such systems are now coming online, with more progress expected in the next few years. We can and should use tools of quantum gravity to describe the physics of these experiments. I will sketch one possible experiment exhibiting nontrivial behavior which, though perfectly understandable in hindsight using conventional methods, is motivated entirely by the physics of wormholes.

        Speaker: Stefan Leichenauer
      • 25
        Hidden Space-times in Quantum Spin Chains

        It has been suggested that space-time geometries can emerge from quantum entanglement in the context of AdS/CFT and beyond. Inspired by travel-time tomography in seismology, we construct a geometry detector that quantitatively determines whether classical space-times can actually emerge from certain entanglement patterns. Then we explicitly reconstruct the best-fit emergent holographic geometries from various entanglement data extracted from a 1-dimensional quantum system, such as a quantum spin chain at criticality, for both static and dynamical cases. Finally, we discuss how this approach may be used for understanding simulated classical/quantum gravitational dynamics in a laboratory setting.

        Speaker: Charles Cao
    • Evening session: Quantum control of oscillators
      • 26
        Precision searches for new physics using optically levitated sensors
        Speaker: David Moore (Yale)
      • 27
        Exploring sensing and quantum measurement with membrane cavity optomechanics
        Speaker: Cindy Regal (University of Colorado)
    • 17:30
      Coffee break
    • Evening session: Qubits and quantum sensing
      • 28
        Quantum metamaterial for nondestructive microwave photon detection

        Detecting traveling photons is an essential primitive for many quantum information processing tasks. We propose a single-photon detector operating in the microwave domain based on a nonlinear metamaterial built from a large number of coupled Josephson junctions. By trading local nonlinearity for large spatial extent, this approach allows for a large detection bandwidth. Using numerical simulations based on many-body physics methods, we show that the single-photon detection fidelity increases with the length of the metamaterial to approaches one. The photon is not destroyed and the photon wavepacket is only minimally disturbed by the detection, in stark contrast to conventional photon detectors operating in the optical domain. The proposed detector thus offers new possibilities for quantum information processing with superconducting qubits, as well as fundamentally new experiments exploring single-photon physics and phenomenology.

        Speaker: Alexandre Blais
      • 29
        TBD
        Speaker: Dave Schuster (Chicago)
      • 30
        HAYSTAC and the Search for Dark Matter Axions above 10 micro-eV
        Speaker: Reina Maruyama (Yale)
    • Morning session: Particle physics and quantum information
      • 31
        Quantum algorithms for pattern recognition in high-energy physics experiments
        Speaker: Heather Gray
      • 32
        Quantum Algorithms for High Energy Physics Simulations
        Speaker: Christian Bauer
    • 09:00
      Coffee break
    • Morning session: New technologies II
      • 33
        Axion Searches from Micro-eV to Milli-eV
        Speaker: Andrew Sonnenschein
      • 34
        First results of DarkSRF: a dark photon search using SRF cavities
        Speaker: Anna Grasselino (Fermilab)
    • Evening session: Towards the future
      • 35
        Panel discussion: Strategies for Advancing QIS and Fundamental Science (Raphael Bousso, Joe Lykken, Yoshihisa Yamamoto, Maria Spiropulu + ...)

        Gathering the perspective of leaders in quantum computing, quantum gravity, HEP theory and experiment. Where do we think each of the fields is going? What are near-term opportunities for cross-fertilization? How can we make best use of the opportunities offered by the National Quantum Initiative, by investments made by industry, and by the HEP Snowmass process? What are the long-term prospects for advancing scientific knowledge and technical capabilities if we are allowed to dream?

        Speakers: Aaron Chou, Joe Lykken (Fermilab), Kathryn Zurek, Konrad Lehnert, Maria Spiropulu (Caltech), Raphael Bousso (Berkeley)