Design and Fabrication of a Chip-based Continuous-wave Atom Laser

TL;DR

This paper presents a novel chip-based design for a continuous-wave atom laser, integrating magnetic guiding and evaporative cooling, with detailed fabrication methods and options for atom interferometry.

Contribution

It introduces a new integrated chip design for a CW atom laser with multiple atom interferometry configurations and demonstrates fabrication techniques using existing microfabrication equipment.

Findings

Successful design of a spiral wire guide with integrated solenoid

Feasibility of fabricating the device with current microfabrication tools

Potential for advanced atom interferometry on a chip

Abstract

We present a design for a continuous-wave (CW) atom laser on a chip and describe the process used to fabricate the device. Our design aims to integrate quadrupole magnetic guiding of ground state Rb atoms with continuous surface adsorption evaporative cooling to create a continuous Bose-Einstein condensate; out-coupled atoms from the condensate should realize a CW atom laser. We choose a geometry with three wires embedded in a spiral pattern in a silicon subtrate. The guide features an integrated solenoid to mitigate spin-flip losses and provide a tailored longitudinal magnetic field. Our design also includes multiple options for atom interferometry: accomodations are in place for laser-generated atom Fabry-Perot and Mach-Zehnder interferometers, and a pair of atomic beam X-splitters is incorporated for an all-magnetic atom Mach-Zehnder setup. We demonstrate the techniques necessary to fabricate our device using existing micro- and nano-scale fabrication equipment, and discuss future options for modified designs and fabrication processes.