QRC Seminar Series - Prof. Martin Kliesch

Title:

Challenges for near term quantum computing

Abstract:

The perspective of using quantum computers to solve otherwise intractable computational problems is naturally exciting for scientists and is also starting to attract substantial industrial interest. The ultimate goal is to build large scale universal quantum computers, which support general quantum algorithms. However, due to daunting requirements regarding error control and qubit numbers this goal currently seems to be out of reach. In the intermediate time, special purpose machines are being developed that can solve at least some task substantially better than classical computers. Their applications range from mere demonstrators of "quantum supremacy" to hybrid quantum-classical algorithms for problems, e.g. from quantum chemistry and classical optimization. 

This talk will start with an introduction to the topic and discuss several challenges. After mentioning the verification challenge of quantum supremacy experiments the focus will be put on hybrid quantum-classical algorithms. It will be shown that the classical computation part can constitute a computationally hard problem. Moreover, the measurement effort and, hence, the effort for the quantum computation can be daunting. Here, a new measurement scheme will be discussed that allows to reduce the measurement effort significantly. In this way, we hope to make progress towards useful advantages of quantum computation.