In late 2018, SBQMI launched a “Grand Challenges” call for proposals open to all institute members. The call was framed around addressing a "grand challenge" currently facing Canadians and the world. Building upon the uniqueness of SBQMI's approach, these projects identify bold ideas that will define our research agenda for the next decade.
Below are the projects that have since evolved out of the original submissions which span the gamut from quantum computation to novel concepts that rethink our approach to entropy.
I. Disorder and Entropy as Design Principles of New Functional Materials
Historically, the discovery of new materials has been driven by two seemingly opposing paradigms. On the one hand, we search for emerging properties and novel behavior by producing ever more perfect and ideal crystals. A prime example is the emergence of high-temperature superconductivity in certain ceramics more than 30 years ago, and the ensuing quest to understand its origin. In this approach, defects and disorder in the crystal structure are considered detrimental and unwanted. On the other hand, the deliberate introduction of defects (for instance chemical doping in semiconductors) can be used to engineer specific electronic material properties. This research program posits to take advantage of the novel and beneficial effects that high disorder and entropy can provide to endow materials with functional properties. The grand challenge consists in identifying and understanding the precise atomic (i.e. quantum) scale mechanisms and conditions under which the different forms of disorder and entropy lead to novel material behaviour.
II. Pushing the Boundaries of Noisy Intermediate Scale Quantum (NISQ) Computing by Focusing on Quantum Materials Problems
When making the leap from a classical computer (e.g. a PC or supercomputer) to a quantum computer, processing logic and physical foundation change in dramatic ways. On the logical side, the elementary unit of information in a quantum computing system changes from bit to qubit, allowing for entirely novel ways of data processing. Will humankind be able to harness the quantum for computation? Will the leap from digital computers to quantum computers be bigger than from analog to digital? While it is too early to give definitive answers to these questions, ideas in quantum computing experimentation are currently being explored. The field is changing from theorists’ fantasy to experimentalists’ reality (and some say, engineers’ nightmare).
There are also some constraints to be addressed. While experimental quantum computing services are open for business, the quantum computers that are currently available or expected to become available in the near future are too small (in terms of information capacity) to support fault-tolerance and therefore, long computations. Therefore, quantum computation on such devices is constrained by decoherence. This constraint is in addition to that imposed by the small number of qubits available for experimentation and research. In short, the question this proposal asks is this: “What can be done with the small-scale quantum computers available now or in the near future?” This is a program and approach that looks at the practical realities of current constraints while imagining the possibilities suggested through the results of quantum algorithmic tests.
III. Engineering exotic phases in two dimensions
The unusual physics of electrons in two dimensions (2D) has given rise to a half-century of novel physics and technology, historically emerging at interfaces between conventional semiconductors. Two breakthroughs in the 2000s dramatically broadened this field. One was the development of methods to grow atomically perfect stacks of less common materials, leading to phenomena such as magnetism and superconductivity that are elusive in semiconductors.
The second was the discovery of graphene, single atomic layers of graphite, resulting in an explosion of work on compounds that could be exfoliated like graphene and assembled into “van der Waals” stacks. Such 2D materials offer access for engineering via a third spatial dimension, either by stacking dissimilar materials or local gating. They are also amenable to study by powerful techniques for probing surfaces, since they are mostly surface.
The field of 2D materials proliferated rapidly thanks to those two discoveries, with the development of new stacking controls such as strain and twisting of layers, and recipes to grow more exotic materials combinations.