By cooling circuits from room temperature to 10,000 times closer to absolute zero, entire circuits enter a quantum mechanical state where quantized energy states can be observed, analogous to those of an atom. While the states of an atom are described spatially, the states of the superconducting circuit are typically described as a function of charge or magnetic flux. The lowest energy states form quantum bits (qubits), which exhibit quantum coherence described by the laws of quantum mechanics unlike classical bits in the computers used today. The useful quantum properties of the qubits decay in time due to decoherence. In this group we are interested in studying the sources of decoherence and improving upon the designs of qubit circuits.