Controllable chip-based beam splitter for cold polar molecules

Abstract

We proposed a $\mathsf{Y}$-shaped molecular beam splitter for guided polar molecules, composed by several 1-\ensuremath{\mu}m-thick gold electrodes deposited on a chip. The splitter has a total length of 10 mm and the height of the electrostatic guiding center (minimum of the electric fields) is about 100 \ensuremath{\mu}m from the surface of the chip. Our theoretical analysis and trajectory calculations are carried out using two types of polar molecules of ammonia-${\mathrm{D}}_{3}$ ($\mathrm{N}{\mathrm{D}}_{3}$) and strontium fluoride (SrF). The calculated results show explicitly that, by applying a few hundred volts on the electrodes, the splitter can direct the guided (light or heavy) polar molecules to either of the two outgoing arms with any desired ratio (from 0% to 100%) by changing the voltages applied on the electrodes. This chip-scale molecular beam splitter offers a platform for molecular optics, precision measurements, and quantum computation. This basic optical element could be integrated into molecular chips and serve as a building block for a future gas-phase molecular laboratory on a chip.