Circuits for Measurement Based Quantum State Preparation

In quantum computing, state preparation is the problem of synthesizing circuits that initialize quantum systems to specific states. It has been shown that there are states that require circuits of exponential size to be prepared (when not using measurements), and consequently, despite extensive research on this problem, the existing computer-aided design (CAD) methods produce circuits of exponential size. In this paper, we show how CAD based state preparation can be made scalable by using techniques that are unique to quantum computing: measurements, and the resulting state collapses. With this approach, we are able to produce wide classes of states in polynomial time, resulting in an exponential improvement over existing CAD methods.