Dual atom (⁸⁷Rb-¹³³Cs) grating magneto-optical trap

This paper proposes a dual-color grating chip design method for simultaneously capturing dual atomic clouds (⁸⁷Rb and ¹³³Cs). By simulating key parameters such as the grating period, etching depth, duty cycle, coating material, and thickness, the optimal design parameters were determined (T = 210 nm, r = 0.5, h₀ = 100 nm, d = 1150 nm) to ensure efficient dual-wavelength diffraction and maximize the number of captured atoms. Experimental results demonstrate the simultaneous trapping of 1.6 × 10⁸⁸⁷Rb atoms and 7.8 × 10⁶¹³³Cs atoms, thereby offering an approach for multi-species cold atom systems. This dual-species grating magneto-optical trap (GMOT) system has potential applications in precision measurements such as cold atom clocks, quantum interferometers, and quantum electrometry.