Quantum Simulators, Boson Sampling and the Quest for Superpolynomial Speedups

Total Page:16

File Type:pdf, Size:1020Kb

Quantum Simulators, Boson Sampling and the Quest for Superpolynomial Speedups Movitation Quantum simulation Speedups Trustworthy simulations Quantum simulators, boson sampling and the quest for superpolynomial speedups Jens Eisert, Freie Universität Berlin With Dom Hangleiter, Martin Schwarz, Robert Raussendorf, Juan Bermejo-Vega ICNFP 2017, Crete, July 2017 Movitation Quantum simulation Speedups Trustworthy simulations Quantum simulators, boson sampling and the quest for superpolynomial speedups ! Recent years have seen rapid development of quantum devices Movitation Quantum simulation Speedups Trustworthy simulations ! Large-scale continuous variable systems Quantum simulators, boson sampling and the quest for superpolynomial speedups Roslund, de Arujo, Jiang, Fabre, Treps, Nature Phot 8, 109 (2014) Menicucci, Flammia, Pfister, Phys Rev Lett 13, 130501 (2008) Yokohama, Ukai, Armstrong, Sornphiphatphong, Kaji, Suziki, Yoshikawa, Yonezawa, Menicucci, Furusawa, Nature Phot 7, 982 (2013) Movitation Quantum simulation Speedups Trustworthy simulations ! Linear optical devices and integrated optics Quantum simulators, boson sampling and the quest for superpolynomial speedups Carolan, Harrold, Sparrow, Martín-López, Russell, Silverstone, Shadbolt, Matsuda, Oguma, Itoh, Marshall, Thompson, Matthews, Hashimoto, O’Brien, Laing, Science 349, 711 (2015) Langford, Kundys, Gates, Smith, Smith, Walmsley, Nature Phot 8, 770 (2014) Movitation Quantum simulation Speedups Trustworthy simulations ! Trapped ions Quantum simulators, boson sampling and the quest for superpolynomial speedups Schindler, Mueller, Nigg, Barreiro, Martinez, Hennrich, Monz, Diehl, Zoller, Blatt, Nature Phys 9, 361 (2013) Movitation Quantum simulation Speedups Trustworthy simulations ! Cold atomic quantum simulators Quantum simulators, boson sampling and the quest for superpolynomial speedups Trotzky, Chen, Flesch, McCulloch, Schollwoeck, Eisert, Kaufman, Tai, Lukin, Rispoli, Schittko, Preiss, Greiner, Bloch, Nature Phys 8, 325 (2012) Science 353, 794 (2016) Movitation Quantum simulation Speedups Trustworthy simulations ! Industrial efforts, mostly on superconducting devices Quantum simulators, boson sampling and the quest for superpolynomial speedups Intel Google D-wave IBM ! When can we expect quantum devices to computationally outperform classical computers? Movitation Quantum simulation Speedups Trustworthy simulations Quantum simulators, boson sampling and the quest for superpolynomial speedups ! When can we expect quantum devices to computationally outperform classical computers? Movitation Quantum simulation Speedups Trustworthy simulations Quantum simulators, boson sampling and the quest for superpolynomial speedups ! (Analog) quantum simulators ! Quantum simulators are promised to solve problems ! How! Howdo we can know they we outperform have done classical the right computers? thing? inaccessible to classical computers ! Not BQP-complete, what is computational power? ! Error correction/fault tolerance unavailable Movitation Quantum simulation Speedups Trustworthy simulations Quantum simulators, boson sampling and the quest for superpolynomial speedups Movitation Quantum simulation Speedups Trustworthy simulations Cold atomic quantum simulators Movitation Quantum simulation Speedups Trustworthy simulations Analog quantum simulators ! Cold atoms in optical lattices allow to probe condensed matter systems 4 5 ! Probe local Hamiltonians, 10 10 particles ⇠ − ! Ground state problems itH itH ! ”Quenches” ⇢ ( t )= e − ⇢ e (time evolution) ! Slow evolutions, driven and open settings Bloch, Dalibard, Nascimbene, Nature Phys 8, 267 (2012) Movitation Quantum simulation Speedups Trustworthy simulations Analog quantum simulators A ! Equilibration and thermalisation of atoms in optical super-lattices (MPQ) ! Imbalance as function of time for (0) = 0 , 1 ,..., 0 , 1 under | i | i Bose-Hubbard Hamiltonian Movitation Quantum simulation Speedups Trustworthy simulations Analog quantum simulators A ! Equilibration and thermalisation of atoms in optical super-lattices (MPQ) ! Imbalance as function of time for (0) = 0 , 1 ,..., 0 , 1 under | i | i Bose-Hubbard Hamiltonian odd n Best available classical matrix-product state simulation, bond dimension 5000 Trotzky, Chen, Flesch, McCulloch, Schollwoeck, Eisert, Bloch, Nature Phys 8, 325 (2012) Movitation Quantum simulation Speedups Trustworthy simulations Analog quantum simulators Equilibration Kibble-Zurek mechanism Many-body localization Short times can be 1D systems can be efficiently simulated, Schreiber, Hodgman, Bordia, Lüschen, Fischer, Vosk, efficiently simulated 2D systems not Altman, Schneider, Bloch, Science 349, 842 (2015) Trotzky, Chen, Flesch, McCulloch, Schollwoeck, Braun, Friesdorf, Hodgman, Schreiber, Eisert, Bloch, Nature Phys 8, 325 (2012) Ronzheimer, Riera, del Rey, Bloch, Eisert, Schneider, Proc Natl Acad Sci 112 3641 (2015) Movitation Quantum simulation Speedups Trustworthy simulations Analog quantum simulators Equilibration Kibble-Zurek mechanism Many-body localization Short times can be 1D systems can be efficiently simulated, Schreiber, Hodgman, Bordia, Lüschen, Fischer, Vosk, efficiently simulated 2D systems not Altman, Schneider, Bloch, Science 349, 842 (2015) Trotzky, Chen, Flesch, McCulloch, Schollwoeck, Braun, Friesdorf, Hodgman, Schreiber, Eisert, Bloch,! Nature Phys 8, 325 (2012) Ronzheimer, Riera, del Rey, Bloch, Eisert, Dynamical quantumSchneider, simulators Proc Natl Acad Sci 112 3641 (2015) Existing quantum simulators outperform state-of-the-art simulations on classical supercomputers ! Cleverer simulation method? Movitation Quantum simulation Speedups Trustworthy simulations Quest for intermediate problems BQP BPP ! Intermediate problems To be sure, we should prove the hardness of the task: Identify a (feasible) task that lies outside of BPP, but is not BQP hard Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial computational speedups Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Dubbed “quantum computational supremacy” Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling 1 1 0 0 0 ! n bosons in m optical modes ! Haar random mode transformation b Ub U U(m) T 7! 2 b =(b1,...,bm) 1 0 0 1 0 ! Photon detection Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling 1 1 0 0 0 ! n bosons in m optical modes ! Haar random mode transformation b Ub T 7! b =(b1,...,bm) 1 0 0 1 0 ! Photon detection Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling 1 1 0 0 0 ! n bosons in m optical modes ! Haar random mode transformation b Ub U U(m) T 7! 2 b =(b1,...,bm) 1 0 0 1 0 ! Photon detection ! Theorem: Sampling from a distribution close in l 1 norm to boson sampling distribution is "computationally hard" with high probability if the unitary U is chosen from Haar 5 measure and m increases sufficiently fast with n ( m ⌦ ( n ) ) 2 Aaronson, Arkhipov, Th Comp 9, 143 (2013) Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling ! 1B eautiful 1 experiments0 0 0 ! n bosons in m optical modes ! Haar random mode transformation b Ub U U(m) T 7! 2 b =(b1,...,bm) 1 0 0 1 0 ! Photon detection ! Theorem: Sampling from a distribution close in l 1 norm to boson sampling distribution is "computationally hard" with high probability if the unitary U is chosen from Haar 5 measure and m increases sufficiently fast Broomewith et n al, Science( m 339, ⌦ 794 ( (2012)n ) ) Spring et al, Science 339,2 798 (2012) Aaronson, Arkhipov, Th Comp 9, 143 (2013) Tillmann et al, Nature Photonics 7, 540 (2013) Crespi et al, Nature Photonics 7, 545 (2013) Bloch, Nature Phys 8, 325 (2012) Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling 1 1 0 0 0 ! n bosons in m optical modes ! Haar random mode transformation b Ub U U(m) T 7! 2 b =(b1,...,bm) 1 0 0 1 0 ! Photon detection Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups! Certification using continuous-variables: ! Target fidelity F ( ⇢ t , ⇢ p ) F T with anticipated state ⇢t ! Aim: Find some problem with strong evidence for super-polynomial≥ speedup ! Boson sampling 1 1 0 0 0 ? 1 FT %p ! n bosons in m optical modes− 1 F %t − ! Haar random mode transformation∆ b Ub U U(m) T 7! 2 b =(b1,...,bm) ! Can perform robust fidelity certfication, with poly(m, 1/∆) O log(1/(1 ↵)) ✓ − ◆ many preparations and homodyne measurements, with success probability Aolita, Gogolin, Kliesch, Eisert, Nature Communications 6, 8498 (2015) ! Great tool, not quite good enough Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence for super-polynomial speedup ! Boson sampling 1 1 0 0 0 ! n bosons in m optical modes ! Haar random mode transformation U U(m) T 2 b =(b1,...,bm) 1 0 0 1 0 Movitation Quantum simulation Speedups Trustworthy simulations Super-polynomial speedups ! Aim: Find some problem with strong evidence
Recommended publications
  • Simulating Quantum Field Theory with a Quantum Computer
    Simulating quantum field theory with a quantum computer John Preskill Lattice 2018 28 July 2018 This talk has two parts (1) Near-term prospects for quantum computing. (2) Opportunities in quantum simulation of quantum field theory. Exascale digital computers will advance our knowledge of QCD, but some challenges will remain, especially concerning real-time evolution and properties of nuclear matter and quark-gluon plasma at nonzero temperature and chemical potential. Digital computers may never be able to address these (and other) problems; quantum computers will solve them eventually, though I’m not sure when. The physics payoff may still be far away, but today’s research can hasten the arrival of a new era in which quantum simulation fuels progress in fundamental physics. Frontiers of Physics short distance long distance complexity Higgs boson Large scale structure “More is different” Neutrino masses Cosmic microwave Many-body entanglement background Supersymmetry Phases of quantum Dark matter matter Quantum gravity Dark energy Quantum computing String theory Gravitational waves Quantum spacetime particle collision molecular chemistry entangled electrons A quantum computer can simulate efficiently any physical process that occurs in Nature. (Maybe. We don’t actually know for sure.) superconductor black hole early universe Two fundamental ideas (1) Quantum complexity Why we think quantum computing is powerful. (2) Quantum error correction Why we think quantum computing is scalable. A complete description of a typical quantum state of just 300 qubits requires more bits than the number of atoms in the visible universe. Why we think quantum computing is powerful We know examples of problems that can be solved efficiently by a quantum computer, where we believe the problems are hard for classical computers.
    [Show full text]
  • Quantum Entanglement Producing and Precision Measurement With
    QUANTUM ENTANGLEMENT PRODUCING AND PRECISION MEASUREMENT WITH SPINOR BECS by Zhen Zhang A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Physics) in the University of Michigan 2015 Doctoral Committee: Professor Luming Duan, Chair Associate Professor Hui Deng Professor Georg A. Raithel Professor Duncan G. Steel Assistant Professor Kai Sun c Zhen Zhang 2015 To my parents and my husband. ii ACKNOWLEDGMENTS I am greatly indebted to my adviser, Professor Luming Duan, for mentoring me over the last six years. He is a wise professor with sharp insights and broad knowledge and also a kind and supportive supervisor. He offered me a lot help and advise both in my research and for my career. It has been my great honor working with him during my doctoral study. I would also like to thank my undergraduate research adviser Professor Mailin Liang , Profes- sor Wusheng Dai and Professor Mi Xie at Tianjin University, China, for guiding me into the world of physics research and offering initial scientific training. I am also grateful to all the other profes- sors who gave me advice and help imparted their knowledge and enthusiasm through classroom teaching or otherwise during the ten years of undergraduate and graduate study. I also benefited tremendously from my group mates and visitors. In particular, Zhexuan Gong who gave me warm welcome and help when I joined the group; Yang-Hao Chan who taught me cold atom physics in the very beginning of my research; Jiang-Min Zhang shared with me a lot of knowledge and experience both in research and in personal life; Dong-Ling Deng and Sheng- Tao Wang discussed with me on many problems.
    [Show full text]
  • Quantum Supremacy
    Quantum Supremacy Practical QS: perform some computational task on a well-controlled quantum device, which cannot be simulated in a reasonable time by the best-known classical algorithms and hardware. Theoretical QS: perform a computational task efficiently on a quantum device, and prove that task cannot be efficiently classically simulated. Since proving seems to be beyond the capabilities of our current civilization, we lower the standards for theoretical QS. One seeks to provide formal evidence that classical simulation is unlikely. For example: 3-SAT is NP-complete, so it cannot be efficiently classical solved unless P = NP. Theoretical QS: perform a computational task efficiently on a quantum device, and prove that task cannot be efficiently classically simulated unless “the polynomial Heierarchy collapses to the 3nd level.” Quantum Supremacy A common feature of QS arguments is that they consider sampling problems, rather than decision problems. They allow us to characterize the complexity of sampling measurements of quantum states. Which is more difficult: Task A: deciding if a circuit outputs 1 with probability at least 2/3s, or at most 1/3s Task B: sampling from the output of an n-qubit circuit in the computational basis Sampling from distributions is generically more difficult than approximating observables, since we can use samples to estimate observables, but not the other way around. One can imagine quantum systems whose local observables are easy to classically compute, but for which sampling the full state is computationally complex. By moving from decision problems to sampling problems, we make the task of classical simulation much more difficult.
    [Show full text]
  • Multi-Photon Boson-Sampling Machines Beating Early Classical Computers
    Multi-photon boson-sampling machines beating early classical computers Hui Wang1,2*, Yu He1,2*,Yu-Huai Li1,2*, Zu-En Su1,2,Bo Li1,2, He-Liang Huang1,2, Xing Ding1,2, Ming-Cheng Chen1,2, Chang Liu1,2, Jian Qin1,2,Jin-Peng Li1,2, Yu-Ming He1,2,3, Christian Schneider3, Martin Kamp3, Cheng-Zhi Peng1,2, Sven Höfling1,3,4, Chao-Yang Lu1,2,$, and Jian-Wei Pan1,2,# 1 Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai, 201315, China 2 CAS-Alibaba Quantum Computing Laboratory, CAS Centre for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, China 3 Technische Physik, Physikalisches Instität and Wilhelm Conrad Röntgen-Center for Complex Material Systems, Universitat Würzburg, Am Hubland, D-97074 Würzburg, Germany 4 SUPA, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom * These authors contributed equally to this work $ [email protected], # [email protected] Boson sampling is considered as a strong candidate to demonstrate the “quantum computational supremacy” over classical computers. However, previous proof-of- principle experiments suffered from small photon number and low sampling rates owing to the inefficiencies of the single-photon sources and multi-port optical interferometers. Here, we develop two central components for high-performance boson sampling: robust multi-photon interferometers with 99% transmission rate, and actively demultiplexed single-photon sources from a quantum-dot-micropillar with simultaneously high efficiency, purity and indistinguishability. We implement and validate 3-, 4-, and 5-photon boson sampling, and achieve sampling rates of 4.96 kHz, 151 Hz, and 4 Hz, respectively, which are over 24,000 times faster than the previous experiments, and over 220 times faster than obtaining one sample through calculating the matrices permanent using the first electronic computer (ENIAC) and transistorized computer (TRADIC) in the human history.
    [Show full text]
  • Quantum Computer-Aided Design of Quantum Optics Hardware
    Quantum computer-aided design of quantum optics hardware Jakob S. Kottmann,1, 2, ∗ Mario Krenn,1, 2, 3, y Thi Ha Kyaw,1, 2 Sumner Alperin-Lea,1, 2 and Al´anAspuru-Guzik1, 2, 3, 4, z 1Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Canada. 2Department of Computer Science, University of Toronto, Canada. 3Vector Institute for Artificial Intelligence, Toronto, Canada. 4Canadian Institute for Advanced Research (CIFAR) Lebovic Fellow, Toronto, Canada (Dated: May 4, 2021) The parameters of a quantum system grow exponentially with the number of involved quantum particles. Hence, the associated memory requirement to store or manipulate the underlying wave- function goes well beyond the limit of the best classical computers for quantum systems composed of a few dozen particles, leading to serious challenges in their numerical simulation. This implies that the verification and design of new quantum devices and experiments are fundamentally limited to small system size. It is not clear how the full potential of large quantum systems can be exploited. Here, we present the concept of quantum computer designed quantum hardware and apply it to the field of quantum optics. Specifically, we map complex experimental hardware for high-dimensional, many-body entangled photons into a gate-based quantum circuit. We show explicitly how digital quantum simulation of Boson sampling experiments can be realized. We then illustrate how to design quantum-optical setups for complex entangled photonic systems, such as high-dimensional Greenberger-Horne-Zeilinger states and their derivatives. Since photonic hardware is already on the edge of quantum supremacy and the development of gate-based quantum computers is rapidly advancing, our approach promises to be a useful tool for the future of quantum device design.
    [Show full text]
  • The Weakness of CTC Qubits and the Power of Approximate Counting
    The weakness of CTC qubits and the power of approximate counting Ryan O'Donnell∗ A. C. Cem Sayy April 7, 2015 Abstract We present results in structural complexity theory concerned with the following interre- lated topics: computation with postselection/restarting, closed timelike curves (CTCs), and approximate counting. The first result is a new characterization of the lesser known complexity class BPPpath in terms of more familiar concepts. Precisely, BPPpath is the class of problems that can be efficiently solved with a nonadaptive oracle for the Approximate Counting problem. Similarly, PP equals the class of problems that can be solved efficiently with nonadaptive queries for the related Approximate Difference problem. Another result is concerned with the compu- tational power conferred by CTCs; or equivalently, the computational complexity of finding stationary distributions for quantum channels. Using the above-mentioned characterization of PP, we show that any poly(n)-time quantum computation using a CTC of O(log n) qubits may as well just use a CTC of 1 classical bit. This result essentially amounts to showing that one can find a stationary distribution for a poly(n)-dimensional quantum channel in PP. ∗Department of Computer Science, Carnegie Mellon University. Work performed while the author was at the Bo˘gazi¸ciUniversity Computer Engineering Department, supported by Marie Curie International Incoming Fellowship project number 626373. yBo˘gazi¸ciUniversity Computer Engineering Department. 1 Introduction It is well known that studying \non-realistic" augmentations of computational models can shed a great deal of light on the power of more standard models. The study of nondeterminism and the study of relativization (i.e., oracle computation) are famous examples of this phenomenon.
    [Show full text]
  • Models of Optical Quantum Computing
    Nanophotonics 2017; 6(3): 531–541 Review article Open Access Hari Krovi* Models of optical quantum computing DOI 10.1515/nanoph-2016-0136 element method [9], and search on graphs for marked ver- Received August 2, 2016; accepted November 9, 2016 tices [10]. All these examples provide evidence that this model of computing is potentially more powerful than Abstract: I review some work on models of quantum com- classical computing. However, it should also be pointed puting, optical implementations of these models, as well out that there is currently no evidence that quantum com- as the associated computational power. In particular, we puters can solve NP-hard problems in polynomial time. discuss the circuit model and cluster state implemen- The class NP stands for nondeterministic polynomial time tations using quantum optics with various encodings (defined more explicitly in the next section) and consists such as dual rail encoding, Gottesman-Kitaev-Preskill of problems whose solution can be checked polynomial encoding, and coherent state encoding. Then we discuss time by deterministic classical computers. The impor- intermediate models of optical computing such as boson tance of this class stems from the fact that several practi- sampling and its variants. Finally, we review some recent cal problems lie in this class. Despite the lack of evidence work in optical implementations of adiabatic quantum of an exponential quantum speed-up for problems in this computing and analog optical computing. We also pro- class, there are a lot of examples where one has a polyno- vide a brief description of the relevant aspects from com- mial speed-up (such as a square-root speed-up) for several plexity theory needed to understand the results surveyed.
    [Show full text]
  • Research Statement Bill Fefferman, University of Maryland/NIST
    Research Statement Bill Fefferman, University of Maryland/NIST Since the discovery of Shor's algorithm in the mid 1990's, it has been known that quan- tum computers can efficiently solve integer factorization, a problem of great practical relevance with no known efficient classical algorithm [1]. The importance of this result is impossible to overstate: the conjectured intractability of the factoring problem provides the basis for the se- curity of the modern internet. However, it may still be a few decades before we build universal quantum computers capable of running Shor's algorithm to factor integers of cryptographically relevant size. In addition, we have little complexity theoretic evidence that factoring is com- putationally hard. Consequently, Shor's algorithm can only be seen as the first step toward understanding the power of quantum computation, which has become one of the primary goals of theoretical computer science. My research focuses not only on understanding the power of quantum computers of the indefinite future, but also on the desire to develop the foundations of computational complexity to rigorously analyze the capabilities and limitations of present-day and near-term quantum devices which are not yet fully scalable quantum computers. Furthermore, I am interested in using these capabilities and limitations to better understand the potential for cryptography in a fundamentally quantum mechanical world. 1 Comparing quantum and classical nondeterministic computation Starting with the foundational paper of Bernstein and Vazirani it has been conjectured that quantum computers are capable of solving problems whose solutions cannot be found, or even verified efficiently on a classical computer [2].
    [Show full text]
  • Arxiv:1412.8427V1 [Quant-Ph] 29 Dec 2014
    Boson Sampling for Molecular Vibronic Spectra Joonsuk Huh,∗ Gian Giacomo Guerreschi, Borja Peropadre, Jarrod R. McClean, and Al´anAspuru-Guziky Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States (Dated: December 30, 2014) Quantum computers are expected to be more efficient in performing certain computations than any classical machine. Unfortunately, the technological challenges associated with building a full- scale quantum computer have not yet allowed the experimental verification of such an expectation. Recently, boson sampling has emerged as a problem that is suspected to be intractable on any classical computer, but efficiently implementable with a linear quantum optical setup. Therefore, boson sampling may offer an experimentally realizable challenge to the Extended Church-Turing thesis and this remarkable possibility motivated much of the interest around boson sampling, at least in relation to complexity-theoretic questions. In this work, we show that the successful development of a boson sampling apparatus would not only answer such inquiries, but also yield a practical tool for difficult molecular computations. Specifically, we show that a boson sampling device with a modified input state can be used to generate molecular vibronic spectra, including complicated effects such as Duschinsky rotations. I. INTRODUCTION a b Quantum mechanics allows the storage and manipula- tion of information in ways that are not possible accord- ing to classical physics. At a glance, it appears evident that the set of operations characterizing a quantum com- puter is strictly larger than the operations possible in a classical hardware. This speculation is at the basis of quantum speedups that have been achieved for oracu- lar and search problems [1, 2].
    [Show full text]
  • Arxiv:2006.09335V1 [Quant-Ph] 16 Jun 2020
    Two-photon interference: the Hong-Ou-Mandel effect Fred´ eric´ Bouchard,1, 2 Alicia Sit,1 Yingwen Zhang,3 Robert Fickler,1, 4 Filippo M. Miatto,5 Yuan Yao,5 Fabio Sciarrino,6 and Ebrahim Karimi1, 3 1Department of Physics, University of Ottawa, Advanced Research Complex, 25 Templeton Street, Ottawa ON Canada, K1N 6N5 2Current address: National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada 3National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada 4Current address: Photonics Laboratory, Physics Unit, Tampere University, Tampere, FI-33720, Finland 5T´el´ecomParis, LTCI, Institut Polytechnique de Paris, 19 Place Marguerite Peray, 91120 Palaiseau, France 6Dipartimento di Fisica, Sapienza Universit`adi Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy Nearly 30 years ago, two-photon interference was observed, marking the beginning of a new quantum era. Indeed, two-photon interference has no classical analogue, giving it a distinct advantage for a range of ap- plications. The peculiarities of quantum physics may now be used to our advantage to outperform classical computations, securely communicate information, simulate highly complex physical systems and increase the sensitivity of precise measurements. This separation from classical to quantum physics has motivated physicists to study two-particle interference for both fermionic and bosonic quantum objects. So far, two-particle inter- ference has been observed with massive particles, among others, such as electrons and atoms, in addition to plasmons, demonstrating the extent of this effect to larger and more complex quantum systems. A wide array of novel applications to this quantum effect is to be expected in the future.
    [Show full text]
  • The 4Th OCU Joint International WS/Seminar on QC/QCC-On-Qcs
    The 4th OCU Joint International WS/Seminar on QC/QCC-on-QCs*,# and WS on AI Applications to Univ. Education/Administration# Date: Mar. 29-30, 2017 Venue: Takahara Memorial Hall, Osaka City University * QC/QCC-on-QCs: Quantum Chemistry/Quantum Chemical Calculations on Quantum Computers Program Note: *Prof. Man-Hong Yung, Department of Physics, South University of Science and Technology, Guangdong Sheng, China won’t be able to come and participate in the WS as an invited speaker this time. # The WS/Seminar has been sponsored by Graduate School of Science, Osaka City University. Invited speakers: Dr. Ryan Babbush, Google Inc., Venice, CA, USA Dr. Jarrod McClean, Lawrence Berkeley National Laboratory, Berkeley, CA, USA Prof. Joonsuk Huh, Department of Chemistry, Sungkyunkwan University, Seoul, Korea Dr. Hiroyuki Nakashima, Quantum Chemistry Research Institute, Kyoto, Japan Dr. Yusaku Kurokawa, Quantum Chemistry Research Institute, Kyoto, Japan Dr. Kenji Sugisaki, Department of Chemistry, Graduate School of Science, Osaka City University Dr. Satoru Yamamoto, Department of Chemistry, Graduate School of Science, Osaka City University Mr. Atsuroh Hiroe, Watson Division, IBM Japan, Ltd., Tokyo, Japan * Prof. Man-Hong Yung, Department of Physics, South University of Science and Technology, Guangdong Sheng, China Session “QC/QCC-on-QCs: Quantum Algorithms” March 29 (Wed.) 9:30-10:45 Dr. Ryan Babbush, Google Inc., Venice, CA, USA "Towards Practical Quantum Chemistry on a Quantum Computer" Outline of the lecture: Abstract As small quantum computers come increasingly close to viability there has been substantial renewed interest in quantum algorithms for modeling chemistry and strongly correlated materials due to low qubit requirements and industrial importance.
    [Show full text]
  • Complexity Theory and Its Applications in Linear Quantum
    Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2016 Complexity Theory and its Applications in Linear Quantum Optics Jonathan Olson Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Physical Sciences and Mathematics Commons Recommended Citation Olson, Jonathan, "Complexity Theory and its Applications in Linear Quantum Optics" (2016). LSU Doctoral Dissertations. 2302. https://digitalcommons.lsu.edu/gradschool_dissertations/2302 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. COMPLEXITY THEORY AND ITS APPLICATIONS IN LINEAR QUANTUM OPTICS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Physics and Astronomy by Jonathan P. Olson M.S., University of Idaho, 2012 August 2016 Acknowledgments My advisor, Jonathan Dowling, is apt to say, \those who take my take my advice do well, and those who don't do less well." I always took his advice (sometimes even against my own judgement) and I find myself doing well. He talked me out of a high-paying, boring career, and for that I owe him a debt I will never be able to adequately repay. My mentor, Mark Wilde, inspired me to work hard without saying a word about what I \should" be doing, and instead leading by example.
    [Show full text]