Dispersive microwave readout for quantum electrical circuits

Summary form only given, as follows. Over the past decade, quantum coherent behavior has been observed in electrical circuits engineered to have discrete, individually addressable energy levels. The basic architecture of a quantum dispersive measurement consisting of a two-level quantum bit coupled to a LC tank circuit is reviewed. Recent progress with this type of readout has led to the real-time monitoring of a superconducting qubit with the observation of individual quantum jumps between energy levels.