A Comparison of Various Classical Optimizers for a Variational Quantum Linear Solver

Understand

Variational Hybrid Quantum Classical Algorithms (VHQCAs) are a class of quantum algorithms intended to run on noisy intermediate-scale quantum (NISQ) devices.

• These algorithms employ a parameterized quantum circuit (ansatz) and a quantum-classical feedback loop.
• A classical device is used to optimize the parameters in order to minimize a cost function that can be computed far more efficiently on a quantum device.
• The cost function is constructed such that finding the ansatz parameters that minimize its value, solves some problem of interest.