Event: Faculty of Science Seminar Series 2023 - 2024
Title: Variational Quantum Algorithms and their Applications
Date: Wednesday, 1 November 2023
Time: 12:00 - 13:00
Venue: Maths & Physics Building, Lab 602 (MP602)
Variational Quantum Algorithms (VQAs) incorporate hybrid quantum–classical computation aimed at harnessing the power of Noisy Intermediate-Scale Quantum (NISQ) computers to solve challenging computational problems.
A brief introduction of quantum computing will be presented first, followed by a discussion on designing a VQA and all of its modules.
We will then delve into one of the applications of VQAs: preparing thermal states on a quantum computer. Thermal states, also known as Gibbs states, have many applications in quantum simulation, quantum optimisation, and quantum machine learning. The main issue in variationally preparing a Gibbs state is the difficulty in measuring the von Neumann Entropy on a quantum device, since it is not an observable quantity.
This issue was entirely alleviated by carefully constructing a parameterised quantum circuit that is able to compute the von Neumann entropy via simple post-processing of computational basis measurements, carried out on ancillary qubits. The preparation of Gibbs states of the Ising model, across a broad range of temperatures, is certified by comparing the fidelity of the prepared state with the exact Gibbs state.
The Speaker
Mirko Consiglio is a theoretical physicist and enthusiastic programmer, with expertise in quantum algorithms, optimization and entanglement. Currently a Research Support Officer working on reinforcement learning for quantum optimal control within the Department of Physics.
Note: For any information about this event email the organiser, Prof. Noel Aquilina, via email.