Events

Quantum mechanics is the most successful theory of physics, giving us the rule book to model phenomenon at the sub-microscopic scale. Knowing the rule book doesn’t necessarily mean it’s easy to follow though. Calculating and modelling quantum systems like complex molecules or materials is computationally demanding for modern computers. However, by mimicking the system of interest with another quantum system, we can explore their properties efficiently and learn a great deal about quantum mechanics itself.

Seminar Presentation by Richard Germond, Queen's University

A number of astrophysical and cosmological observations suggest that roughly 85% of the matter in the Universe is composed of dark matter, presumed to be a particle outside the standard model of particle physics. Direct detection experiments look for signatures of a dark matter particle scattering with a sensitive detector; of the different technologies used for this, cryogenic detectors are well-suited for detecting low-mass dark matter due to their low energy thresholds.

Introduction to Majorana Topological Qubits

Abstract: This presentation will introduce some of the experimental approaches to building topological qubits and the theories supporting current research. Beginning from the early toy models that first proposed the formation of Majorana bound states, I aim to convey an understanding of why topological qubits are so resistant to decoherence. I will introduce the “ingredients” necessary to build a Majorana device and some of the challenges involved. Finally, I will discuss the field's current state and what might be next on the journey to making topological quantum computing a reality. Neither an understanding of topology nor quantum algorithms are necessary to enjoy this talk!

IQC Math and CS Seminar on ZOOM - Featuring Chinmay Nirkhe - IBM

Quantum states wear many hats in quantum information: they simultaneously generalize distributions from classical complexity theory, describe quantum mechanical phenomena, and capture the complexity of quantum computation. This myriad of roles makes understanding the complexity of quantum states a central question in quantum complexity theory. In this talk, we will explore the complexity of classically describing physically relevant quantum states. ...

IQC Math CS Seminar - featuring Mario Szegedy, Rutgers University

Motivated by quantum network applications over classical channels, we initiate the study of n-party resource states from which LOCC protocols can create EPR-pairs between any k disjoint pairs of parties. ...

Chemistry Seminar Series – Steve Winter, Wake Forest University

Host: A. Wei Tsen

Quantum materials represent a broad class of systems whose experimental response relies directly on entanglement between their underlying degrees of freedom. Modeling of such materials presents a variety of challenges related to a disparate variety of complex behaviours that manifest at different energy scales, and a typical sensitivity of responses to model parameters. In this field, first-principles approaches often provide a vital bridge between experiments and theoretical models. In this talk, I will introduce our numerical strategies for systematically building low-energy models with local charge, spin, and orbital degrees of freedom of arbitrary complexity. I will discuss the insights that these methods have yielded for frustrated magnetic insulators collectively known as "Kitaev materials", which have prompted a recent explosion of interest in quantum magnets where spin-orbit coupling induces strongly anisotropic and competing magnetic interactions. I will specifically address our recent attempts to understand the magnetic models of few-layer RuCl3 and high-spin d7 Co(II) compounds, which have recently been identified as possible alternative platforms for realising the celebrated Kitaev model.

Math/CS Seminar Featuring Cihan Okay Bilkent University

In modern homotopy theory, spaces are represented by combinatorial models called simplicial sets. Their elegant formulation gives them great expressive power to capture spaces up to homotopy. Simplicial distributions are basic mathematical objects that mix simplicial sets with probabilities. ...

IQC Colloquium Featuring Dr. Stephanie Simmons - Photonic

The future global quantum internet will require high-performance matter-photon interfaces. The highly demanding technological requirements indicate that the matter-photon interfaces currently under study all have potentially unworkable drawbacks, and there is a global race underway to identify the best possible new alternative. For overwhelming commercial and quantum reasons, silicon is the best possible host for such an interface. Silicon is not only the most developed integrated photonics and electronics platform by far, isotopically purified silicon-28 has also set records for quantum lifetimes at both cryogenic and room temperatures ...

IQC Colloquium Featuring Anupam Mazumdar, University of Groningen

We are led to create a massive and large spatial quantum superposition to probe the quantum nature of gravity in a laboratory. In particular, to witness the quantum entanglement mediated via the quantum nature of gravity, we will need to prepare a pure quantum state of mass 10^{-15} -10^{-14}Kg with a spatial quantum superposition of 10-100 microns and a coherence time of nearly 1-2 seconds. ...

MATH CS Seminar Featuring Maris Ozols, ASSISTANT PROFESSOR UNIVERSITY OF AMSTERDAM QuSoft

Majority vote is a basic method for amplifying correct outcomes that is widely used in computer science and beyond. While it can amplify the correctness of a quantum device with classical output, the analogous procedure for quantum output is not known. We introduce quantum majority vote as the following task: given a product state ∣ψ_1⟩⊗⋯⊗∣ψ_n⟩ where each qubit ∣ψ_i⟩ is in one of two orthogonal states ∣ψ⟩ or ∣ψ^⊥⟩, output the majority state. We show that an optimal algorithm for this problem achieves worst-case fidelity of 1/2 + Θ(1/n). Under the promise that at least 2/3 of the input qubits are in the majority state, the fidelity increases to 1 − Θ(1/n) and approaches 1 as n increases. ...