Power-efficient 3-wave mixing Josephson parametric amplifier*

Josephson Parametric Amplifiers (JPAs) are commonly used in superconducting quantum information processing. A JPA is powered by an rf pump, which typically is orders of magnitude stronger than its output signal. Increasing signal power handling of JPAs would generally require stronger pump. However, the maximum pump power we are able to deliver is limited by the thermalization of the wiring linking the amplifier to room temperature. To address this limitation, we have engineered strong coupling of the off-resonance pump in a 3-wave mixing JPA. Compared to similar JPAs with a capacitively coupled pump port or mutual-inductively coupled flux-pumping, this technique improves power efficiency by at least an order of magnitude without lowering dynamic range and noise performance. Preliminary experimental results will be shown.