Quantum computing

Thursday, August 9, 2018 1:00 pm - 1:00 pm EDT (GMT -04:00)

Quantum computing at Alibaba Group

Yaoyun Shi, Director, Alibaba Quantum Laboratory (AQL)

I will take this opportunity to share with the Waterloo quantum community the thinkings behind Alibaba Group's quantum computing program and our main activities. Questions and comments from the audience are welcome.

About the speaker: Yaoyun Shi is a computer scientist trained at Beijing University, Princeton, and Caltech. He taught at University of Michigan before moving to Alibaba to launch its quantum computing program.

Thursday, May 31, 2018 2:30 pm - 2:30 pm EDT (GMT -04:00)

Scaling up superconducting quantum computers

David P. Pappas, National Institute of Standards and Technology (NIST)

A brief history and overview of the requirements to guide the research and development for high-coherence superconducting quantum circuits will be given. The main focus will be on materials development at NIST. Topics will include identifying and mitigating loss due to amorphous two-level systems at interfaces and how to scale the fabrication of small aluminum-oxide tunnel junctions. The junctions were studied with atom probe microscopy to get an understanding of where the oxidation occurs.

Tuesday, April 24, 2018 2:00 pm - 2:00 pm EDT (GMT -04:00)

Quantum Computing - A Quantum Algorithm for Simulating Non-sparse Hamiltonians

PhD Seminar

Chunhao Wang, PhD candidate

David R. Cheriton School of Computer Science

We present a quantum algorithm for simulating the dynamics of Hamiltonians that are not necessarily sparse. Our algorithm is based on the assumption that the entries of the Hamiltonian are stored in a data structure that allows for the efficient preparation of states that encode the rows of the Hamiltonian. We use a linear combination of quantum walks to achieve a poly-logarithmic dependence on the precision. 

Friday, April 20, 2018 11:45 am - 11:45 am EDT (GMT -04:00)

RAC1 Journal Club/Seminar Series

Keysight's Quantum Engineering Toolkit: A commercial, customizable integrated control and test system

Presented by guest speaker Nizar Messaoudi, Keysight Technologies Application Engineer

With traditional classical complementary metal oxide semiconductor (CMOS) computing struggling to keep up with Moore’s law, interest in quantum computing has exploded and the University of Waterloo is at the centre of this technological revolution.

Tuesday, April 10, 2018 1:30 pm - 1:30 pm EDT (GMT -04:00)

Spatial noise filtering through error correction for quantum sensing

David Layden - Massachusetts Institute of Technology (MIT)

Sensors based on quantum effects can measure various external quantities, such as magnetic fields, with high precision. Moreover, their sensitivity can scale more favourably with their size than is allowed classically — a property analogous to quantum speedups in computing. As with quantum computers, the performance of quantum sensors is limited by decoherence. Quantum error correction (QEC) has recently emerged as a promising approach to mitigate this decoherence, and therefore, to enhance sensitivity.

Wednesday, April 4, 2018 10:30 am - 10:30 am EDT (GMT -04:00)

‘Free-space’ Chiral Quantum Optics and a ‘Few-Atom’ Quantum Antenna

Peter Zoller - University of Innsbruck

We start with an overview of chiral quantum optics as quantum light-atom interfaces with broken left- right symmetry and associated quantum optical phenomena and applications. While chiral quantum optics is traditionally discussed in context of nano-photonics and nano fibers , we propose here a novel ‘free-space’ chiral quantum optics realized as atoms in free space coupled to a ‘few-atom’ quantum antenna. In particular, we discuss free space photonic quantum links between atoms (qubits) equipped with sending and receiving quantum antennas.

Tuesday, March 13, 2018 2:00 pm - 2:00 pm EDT (GMT -04:00)

Solution to a Long-Standing Controversy in Paul-Trap Physics

Angus Kan, Wesleyan University

The study of charged particles dynamics in a Paul trap is the foundation of its wide-ranging applications, including analyzing proteins, determining isotope ratios, and constructing a quantum computer. However, in the simplest case of two-particle dynamics, there remains a controversy on whether a two-ion planar crystal undergoes an order-to-chaos transition at a critical, well-defined trap parameter value. Via analytical and numerical investigation of the Mathieu-Coulomb equations, I show that the transition does not exist.

Friday, February 9, 2018 11:45 am - 11:45 am EST (GMT -05:00)

RAC1 Journal Club/Seminar Series

Kyle Willick: Carbon Nanotube Mechanical Resonators - Magnetic force detection and fast sensing

Kyle WillickSuspended carbon nanotube (CNT) resonators have demonstrated excellent sensitivity in mass and force sensing applications to date. I will introduce these mechanical resonators, and how they can be combined with magnetic field gradients to realize magnetic moment readout.

Monday, March 5, 2018 2:30 pm - 2:30 pm EST (GMT -05:00)

The Quest for Solving Quantum Chromodynamics: the tensor network approach

Colloquium featuring Karl Jansen - NIC/DESY Zeuthen, Germany

The strong interaction of quarks and gluons is described theoretically within the framework of Quantum Chromodynamics (QCD). The most promising way to evaluate QCD for all energy ranges is to formulate the theory on a 4 dimensional Euclidean space-time grid, which allows for numerical simulations on state of the art supercomputers. We will review the status of lattice QCD calculations providing examples such as the hadron spectrum and the inner structure of nucleons.