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A new approach to detecting and diagnosing faults in quantum circuits is introduced. In order to account for the probabilistic nature of quantum circuits, collections of test experiments, called binary tomographic tests (BTTs), are generated. A BTT can identify a fault with respect to some user-defined confidence threshold τ. We present an algorithm to generate BTTs that either detect, or ensure the absence of, all modeled faults in a given circuit. We also present an adaptive diagnostic method to locate quantum faults. While classical circuits, even probabilistic ones, only handle ordinary probabilities, quantum circuits deal with quantum states, which have phase as an extra probabilistic parameter. The tomographic testing methods introduced previously for probabilistic circuits are unable to detect differences in phase, and therefore leave many quantum faults undetected. In contrast, we develop a design-for-test method which is specifically intended to detect faults that only affect the phase of a quantum state. We give experimental results for benchmark and random circuits which show high coverage of quantum faults by BTTs, and good resolution in the case of the adaptive diagnosis method. [ABSTRACT FROM PUBLISHER]

Summary form only given. This special session will introduce the field to the design automation and test community, focusing on recent developments. The ultimate objective of the session is to initiate a dialogue with quantum informatics community by identifying open problems from quantum informatics which can be tackled by design automation methods such as synthesis, optimisation and verification. Among the four speakers are physicists as well as design automation researchers already working on problems from the quantum informatics domain. The first talk of the session will be given by Professor Rodney Van Meter of Keio University, Fujisawa. He will introduce quantum circuits, focusing on the non-trivial aspects of estimating the implementation cost of a given quantum circuit. Such metrics, which roughly correspond to the circuit?s area in the classical domain, will be of highest importance for any quantum circuit optimisation algorithm. Professor Simon Devitt of the National Institute of Informatics, Tokyo, will introduce the concept of topological quantum computing, which is the foundation of most recent scalable quantum circuit implementations. The third speaker, Professor Shigeru Yamashita of Ritsumeikan University, Shiga, will present his recent results on circuit-level optimisation of topological quantum circuits. The problem instances are mapped to a graph, and the optimisation is performed by identifying maximal cliques in this graph. Finally, Professor Austin Fowler of University of Melbourne will speak on recent developments in quantum error correcting codes and classical challenges that arise in this domain. The first three presentations have accompanying papers that are included in the proceedings. [ABSTRACT FROM PUBLISHER]