  This paper provides a comprehensive overview of the development of
flux-driven Josephson Parametric Amplifiers (JPAs) as Quantum Noise Limited
Amplifier for axion search experiments conducted at the Center for Axion and
Precision Physics Research (CAPP) of the Institute for Basic Science. It
focuses on the characterization, and optimization of JPAs, which are crucial
for achieving the highest sensitivity in axion particle detection. We discuss
various characterization techniques, methods for improving bandwidth, and the
attainment of ultra-low noise temperatures. JPAs have emerged as indispensable
tools in CAPPs axion search endeavors, playing a significant role in advancing
our understanding of fundamental physics and unraveling the mysteries of the
universe.
