Quantum computing

Spring School on Quantum Computation

  • By Burcu Ozden
  • 24 January 2018

The 3.5-day Spring school will bring TCS researchers up to speed on the current excitement in quantum computing. The past decade had marked tremendous experimental progress, from one or two-qubit devices to dozens of qubits and more. What are the theoretical models for such devices, and what are their prospects? Can they be classically simulated, and if not, can they accomplish algorithmic speed-ups? What are the obstacles to full-blown fault-tolerant quantum computation? And what does all this tell us about complexity theory, cryptography, and quantum information?

International Conference on Quantum Communication, Measurement and Computing (QCMC)

  • By Leena Aggarwal
  • 8 January 2018

The International Conference on Quantum Communication, Measurement and Computing (QCMC) was established in 1990 to encourage and bring together scientists and engineers working in the interdisciplinary field of quantum information science and technology.

To date, thirteen such meetings have been held and the fourteenth is being organized by Quantum Science and Technologies Group (QST)Louisiana State University on March 12-16, 2018. QST group conducts research on atomic, molecular, and optical physics, the foundations of quantum mechanics, photonic band gap and meta materials, quantum information theory, quantum complexity theory, quantum error correction, quantum optics, optical quantum computing, quantum sensors, quantum imaging, and relativistic quantum information theory. It collaborates with a number of university and industrial research groups around the world, and we receive financial support for our research from a number of sources.

Quantum Computing Summer School Fellowship

  • By Burcu Ozden
  • 20 December 2017

The Quantum Computing Summer School is an immersive 10-week curriculum that includes tutorials from world-leading experts in quantum computation as well as one-on-one mentoring from Los Alamos National Laboratory (LANL) staff scientists who are conducting cutting-edge quantum computing research. Summer school fellowship recipients will be exposed to the theoretical foundations of quantum computation and will become skilled at programming commercial quantum computers, such as those developed by D-Wave Systems and IBM. Ten students will be awarded a fellowship from LANL that covers travel, living expenses in Los Alamos, and salary, with a fellowship value ranging from $7,500 to $13,000, based on academic rank (junior, senior, 1st year graduate student, etc.).

Sergey Frolov Among 2017 Young Investigator Award Recipients

  • By Aude Marjolin
  • 22 February 2017

The Office of Naval Research has announced awards of $16 million through its 2017 Young Investigator Program (YIP). The awards were made to 33 scientists whose research holds strong promise across several naval-relevant science and technology areas.

Sergey Frolov was among this year's Young Investigator Award recipients for his proposal "Semiconductor Nanowire-Based Quantum Emulators".

Applications of Adiabatic Quantum Computation in Mathematical Optimization

Pooya Ronagh
Friday, October 28, 2016 - 1:30pm to 3:00pm

Adiabatic quantum computation (AQC) is one of the paradigms of quantum computation that has recently gained great attention by advancements in manufacturing superconducting qubits. In this talk, I will overview the advantages and limitations of quantum annealers and methods of simulation of the behavior of futuristic devices. I will then discuss applicability of AQC in solving integer programming problems using a branch and bound framework implemented on a hybrid of a digital and a quantum processor.

Quantum Information Processing with 4 Electrons and 10^6 Nuclei

John Nichol
Tuesday, November 15, 2016 - 1:00pm to 2:00pm

Individual spins in semiconductors can retain their quantum phase coherence for times exceeding one second. Such long coherence times makes spins a versatile platform for exploring quantum information processing and condensed matter physics. I will discuss recent work exploiting the joint spin-state of two electrons in a GaAs double quantum dot as a spin qubit. This qubit is highly sensitive to its local magnetic environment. We leverage this sensitivity to precisely measure the statistically fluctuating nuclear polarization in the semiconductor crystal....

Decoherence and Flux Noise in Fluxonium-based Qubits

Angela Kou
Thursday, October 13, 2016 - 4:00pm to 5:00pm

Superconducting qubits are created by connecting Josephson junctions, which are non-linear, non-dissipative elements,to simple electrical circuits. In this talk, I will give a brief introduction to the fluxonium qubit, which is a Josephson junction connected to a superinductance. I will then introduce an artificial molecule, composed of two strongly coupled fluxonium atoms, which possesses a tunable magnetic moment. Using an applied external flux,we can tune the molecule between two regimes: one in which the ground-excited state manifold has a magnetic dipole...

Quantum Physicist Professor Rainer Blatt on the Second Quantum Revolution

  • By Aude Marjolin
  • 1 July 2016

Is quantum technology the future of the 21st century?

On the occasion of the 66th Lindau Nobel Laureate Meeting, this is the key question to be explored today in a panel discussion with the Nobel Laureates Serge Haroche, Gerardus 't Hooft, William Phillips, and David Wineland. In the following interview, Professor Rainer Blatt, internationally renowned quantum physicist, recipient of numerous honours, Council Member and Scientific Co-Chairman of the 66th Lindau Meeting, talks about what we can expect from the "second quantum revolution".

Department of Physics and Astronomy, University of Pittsburgh
Ph.D., Physics, University of Illinois Urbana-Champaign, 2005

I am an experimentalist in the field of condensed matter physics. I study electrical properties of nanometre-size objects. As we find ways  to shrink one, two or all three dimensions of a solid, insights into how nature works on the scale of single electrons get uncovered. Along come prospects of smaller, faster and fundamentally different electronic devices. A spin computer or a quantum computer are examples. Nanofabrication makes it possible to attach electrodes to individual molecules or build artificial atoms. Novel materials such as graphene and semiconductor nanowires contribute previously unattainable properties to our toolbox. At TU Delft I investigate spin physics in nanowire quantum dots and superconductivity induced in semiconductors. In 2012 I move to the University of Pittsburgh, where I am now building a low temperature quantum transport laboratory.

Most Cited Publications
  1. "Signatures of Majorana Fermions in Hybrid Superconductor-Semiconductor Nanowire Devices," V. Mourik, K. Zuo, S. M. Frolov, S. R. Plissard, E. P. A. M. Bakkers, L. P. Kouwenhoven, Science 25, 1003 (2012)
  2. "Spin–orbit qubit in a semiconductor nanowire," S. Nadj-Perge, S. M. Frolov, E. P. A. M. Bakkers & L. P. Kouwenhoven, Nature 468, 1084 (2010)
  3. "New perspectives for Rashba spin–orbit coupling," A. Manchon, H. C. Koo, J. Nitta, S. M. Frolov & R. A. Duine, Nature Materials 14, 871 (2015)
  4. "Spectroscopy of Spin-Orbit Quantum Bits in Indium Antimonide Nanowires," S. Nadj-Perge, V. S. Pribiag, J. W. G. van den Berg, K. Zuo, S. R. Plissard, E. P. A. M. Bakkers, S. M. Frolov, and L. P. Kouwenhoven, Phys. Rev. Lett. 108, 166801 (2012)
  5. "Measurement of the current-phase relation of superconductor/ferromagnet/superconductor π Josephson junctions," S. M. Frolov, D. J. Van Harlingen, V. A. Oboznov, V. V. Bolginov, and V. V. Ryazanov, Phys. Rev. B 70, 144505 (2004)
Recent Publications
  1. "Mirage Andreev Spectra Generated by Medoscopuc Leads in Nanowire Quntum Dots." Su, Z., Zarassi, A., Hsu, J.-F., (...), Bakkers, E.P.A.M., Frolov, S.M. Physical Review Letters (2018).
  2. "Control and detection of Majorana bound states in quantum dot arrays." Stenger, J.P.T., Woods, B.D., Frolov, S.M., Stanescu, T.D. Physical Review B 98(8), 085407 (2018).
  3. "Andreev mlecules in semiconductor nanowires double quantum dots." Su, Z., Tacla, A.B., Hocevar, M., (...), Pekker, D., Frolov, S.M. Nature COmmunications 8(1), 585 (2017).
  4. "Supercurrent Interference in Few-Mode Nanowire Josephson Junctions." Zuo, K., Mourik, V., Szombati, D.B., (...), Kouwenhoven, L.P., Frolov, S.M. Physical Review Letters 119(18), 187704 (2017).
  5. "Quasiballistic quantum transport through Ge/Si core/shell nanowires." Kotekar-Patil, D., Nguyen, B.-M., Yoo, J., Dayeh, S.A., Frolov, S.M. Nanotechnology 28(38), 385204 (2017).