peaker: Lukasz Cincio (LANL)
 
Title:  Quantum algorithms for near-term quantum computers
 
Abstract:
Quantum computers promise to revolutionize many fields, from drug development and material design to solving complex optimization tasks. Large-scale fault-tolerant quantum computers that could achieve such tasks will likely not be available for several years. Current quantum computers are noisy. The information stored in qubits is gradually distorted as it is being processed. To make the best use of those computers, the paradigm of constructing quantum algorithms needs to be changed. Proving correctness is no longer enough, the algorithm needs to use the precious quantum resources to the maximum extent. The most promising strategy is to delegate some of the computation to the classical computer and to leave only the inherently quantum task to the noisy quantum computer. That division is typically done in the framework of hybrid variational quantum-classical algorithms. Here, one considers parametrized quantum circuits that are optimized on classical computers until a desired outcome is achieved. In my talk, I will describe that approach and concentrate on physically motivated examples, such as extracting ground states and low lying excitations of physical and chemical systems. I will also discuss hybrid algorithms for studying real-time dynamics of physical systems. Finally, I will discuss applications of hybrid quantum-classical algorithms to other areas and describe the algorithms for solving linear systems of equations and general purpose automatic generation of short-depth quantum circuits.