Efficient quantum state preparation using Stern-Gerlach effect on cold atoms

TL;DR

This paper demonstrates an efficient method for preparing specific quantum states of cold atoms using the Stern-Gerlach effect, enabling high-fidelity optical pumping and trapping of $^{87}Rb$ atoms.

Contribution

The study introduces a Stern-Gerlach based technique for quantifying and optimizing atomic state preparation in cold atom clouds, achieving 92% efficiency in state preparation.

Findings

Achieved 92% optical pumping efficiency to a specific hyperfine state.

Demonstrated separation and detection of Zeeman states using Stern-Gerlach effect.

Optimized optical pumping process for cold $^{87}Rb$ atoms near an atom-chip.

Abstract

The Zeeman hyperfine state dependent force in a Stern-Gerlach (SG) experiment has been exploited to separate and detect atoms having different Zeeman hyperfine states in a cold atom cloud. Utilizing this SG technique, we have made the quantitative estimate of atoms in different Zeeman hyperfine states in an atom cloud, which has been helpful in optimizing the optical pumping of atoms for efficient preparation of atomic state. Employing an optimized optical pumping, nearly $92 \% $ of cold $^{87}Rb$ atoms from a grey magneto-optical trap (G-MOT) on atom-chip have been optically pumped to the trappable Zeeman hyperfine state $\ket{F=2, \, m_{F} = +2}$. These optically pumped atoms have been trapped in an Ioffe-Pritchard magnetic trap near the atom-chip surface.