This white paper introduces a new class of very high input analog bandwidth and high sampling rate track and hold amplifiers (THAs) has been developed for the test and measurement, Automatic Test Equipment (ATE), digital receivers, and radar systems using a commercially available Indium Phosphide (InP) technology. The newly developed THAs achieved an analog input bandwidth of 12 GHz at 1-Vpp input and a sampling rate as high as 2 GS/s.