Development of a power feeding circuit for RF Carpet

Abstract: The power-feeding circuit supplies an electric field to the radiofrequency (RF) carpet inside a cryogenic gas cell and plays a key role in ion transport. Based on the principle and technical requirements of the multi‑phase RF ion surfing method, we designed a set of system consisting of a signal generator, two power amplifiers, a phase‑splitting circuit and a resonant circuit, which enables fast ion transmission with high efficiency. Test results show that at the resonant frequency of 5.05 MHz, the voltage standing wave ratio is 1.41, the reflected power is below 3%, the RF amplitude reaches 160Vpp and the phase difference is 90.00±0.20°. At room temperature, with the helium gas pressure of 50 mbar, the RF amplitude of 90Vpp, and the push field voltage of 150 V, the ion transport efficiency reaches nearly 60% that verifies the feasibility of the circuit design. This work provides technical supports for optimizing cryogenic gas cell in MRTOF-MS and thus studying exotic nuclides with short half-lives.