Seminar

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).

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.

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.

Tobias Fritz, Perimeter Institute

Similar to how commutative algebra studies rings and their ideals, the protagonists of real algebra are ordered rings. Their interplay between algebra and geometry is studied in terms of Positivstellen- stze, real analogs of the Nullstellensatz, which go back to Artin's solution of Hilbert's 17th problem. I will describe some of the state of the art in this eld, and then introduce a new Positivstellensatz which unies and generalizes several of the existing ones.

John Wright, Massachusetts Institute of Technology (MIT)

In the area of quantum state learning, one is given a small number of "samples" of a quantum state, and the goal is use them to determine a feature of the state. Examples include learning the entire state ("quantum state tomography"), determining whether it equals a target state ("quantum state certification"), or estimating its von Neumann entropy. These are problems which are not only of theoretical interest, but are also commonly used in current-day implementation and verification of quantum technologies.

Joel Wallman, University of Waterloo

Significant global efforts are currently underway to build quantum computers. The two main goals for near-term quantum computers are finding and solving interesting problems in the presence of noise and developing techniques to mitigate errors. In this talk, I will outline and motivate an abstraction layer needed to reliably operate quantum computers under realistic noise models, namely, a cycle consisting of all the primitive gates applied to a quantum computer within a specified time period.

Kun Fang, University of Cambridge

As a more general form of quantum superposition, quantum coherence represents one of the most fundamental features that set the difference of quantum mechanics from the classical realm. In this talk, we will use the tool of semidefinite programming to study two fundamental tasks relating quantum coherence, i.e., coherence distillation of quantum states and coherence cost of quantum processes.

Peter Schumacher, Saarland University

We present an efficient gap-independent cooling scheme for a quantum annealer that benefits from finite temperatures.

An introduction to making scientific figures with Illustrator and Blender

Special guest speaker: Christopher Gutierrez, University of British Columbia

Scientific research can be a slow and laborious process. The absolutely final step in the process is to then communicate your exciting scientific findings to other scientists both in and outside of your field. Yet it is often at this final step where the least amount of time is spent.

Speaker: Rahul Deshpande

Title: Dynamic nuclear polarization in phosphorus doped silicon