Events

Journal club presentation:

"Experimental superposition of orders of quantum gates" by Procopio et. al.

(Nature Comms 6, 7913 (2015)

Arash Ahmadi, Institute for Quantum Computing

Quantum computers achieve a speed-up by placing quantum bits (qubits) in superpositions of different states. However, it has recently been appreciated that quantum mechanics also allows one to ‘superimpose different operations’.

Candidate: Guofei Long

Supervisors: David Cory and Guo-Xing Miao

Adina Luican-Mayer, University of Ottawa

Innovative technologies have a history of capitalizing on the discovery of new physical phenomena, often at the confluence of advances in material characterization techniques and innovations in design and controlled synthesis of high-quality materials. Pioneered by the discovery of graphene, atomically thin materials (2D materials) hold the promise for realizing physical systems with distinct properties, previously inaccessible.

Chinmay Nirkhe, University of California, Berkeley

We study approximate quantum low-density parity-check (QLDPC) codes, which are approximate quantum error-correcting codes specified as the ground space of a frustration-free local Hamiltonian, whose terms do not necessarily commute. Such codes generalize stabilizer QLDPC codes, which are exact quantum error-correcting codes with sparse, low-weight stabilizer generators (i.e. each stabilizergenerator acts on a few qubits, and each qubit participates in a few stabilizer generators).

Speaker: Jacqueline Armstrong Gates

Nicole Yunger Halpern, Harvard University Department of Physics

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, and out-of-equilibrium. Nineteenth-century thermodynamics requires updating for the 21st century. Guidance has come from the mathematical toolkit of quantum information theory.

Nicole Yunger Halpern, Harvard-Smithsonian Institute for Theoretical Atomic, Molecular, and Optical Physics

Join us in QNC 1201 for a Meet and Greet with Nicole Yunger Halpern, Postdoctoral Fellow at the Harvard-Smithsonian Institute for Theoretical Atomic, Molecular, and Optical Physics (ITAMP). All are welcome. Snacks and refreshments will be provided.

Supartha Podder, University of Ottawa

In 2011 Harry Buhrman, Serge Fehr, Christian Schaffner and Florian Speelman proposed a new measure of complexity for finite Boolean functions, called "The Garden-hose complexity". This measure can be viewed as a type of distributed space complexity where two players with private inputs compute a Boolean function co-operatively. While its motivation mainly came from the applications to position based quantum cryptography, the playful definition of the model is quite appealing in itself.

Martin Savage, Institute for Nuclear Theory 

Recently, Silas Beane, David Kaplan, Natalie Klco and I considered the entanglement power of the S-­‐matrix describing low-­‐energy hadronic interactions, and the implications of particular limits. We found that vanishing entanglement power occurs at points of emergent global symmetries, which are seen to be consistent with nature and also recent lattice quantum chromodynamics (QCD) calculations. I will discuss aspects of these results.

Jeremie Roland - Ecole Polytechnique de Bruxelles

We investigate weak coin flipping, a fundamental cryptographic primitive where two distrustful parties need to remotely establish a shared random bit. A cheating player can try to bias the output bit towards a preferred value. For weak coin flipping the players have known opposite preferred values. A weak coin-flipping protocol has a bias ϵ if neither player can force the outcome towards their preferred value with probability more than 1/2+ϵ.