Accessible Quantum Optics: Low-Cost UHV Optical Traps for Rubidium-Based Qubit Manipulation.

Optical traps based on Rb atoms are a great way for undergraduate students to learn about quantum computing. However, expensive specialty equipment prevents undergraduates from accessing them in their labs. We propose a low-cost approach to building optical traps. A vacuum chamber was built using Borofloat glass plates, with Torr Seal epoxy used to bond the pieces together, which gave vacuum integrity with optical access at significantly lower costs. A base pressure in the range of 10⁻⁶ hPa was achieved with a turbomolecular pump; the ion pump was operated by a custom-built 7 kV, 3 mA high-voltage power supply to obtain pressures near 10⁻⁹ hPa. By maintaining UHV pressures in the 10⁻⁹ hPa range and cryogenic temperatures, thermal motion of the Rb atoms is minimized, and their quantum properties are revealed. Thus, one can isolate electron and hyperfine states and use them as qubits for quantum information applications. Atomic physics experiments depend on UHV technologies. These pressures are necessary to confine atomic systems and perform quantum-level manipulations. Future work will center on introducing Rb atoms via a getter source and exciting them coherently with a frequency-stabilized laser using optical components to tune it to the exact excitation wavelength. This approach shows that complex quantum optics and atomic physics experiments can be done within a low-cost, student-built platform, opening the opportunity for quantum science research and education for undergraduate students.