A cavity loadlock apparatus for next-generation quantum optics experiments.

Cavity quantum electrodynamics (QED), the study of the interaction between quantized emitters and photons confined in an optical cavity, is an important tool for quantum science in computing, networking, and synthetic matter. In atomic cavity QED, this approach typically relies upon an ultrahigh vacuum chamber that hosts a cold trapped atomic ensemble and an optical cavity. Upgrading the cavity necessitates a months-long laborious process of removing external optics, venting, replacing the resonator, baking, and replacing optics, constituting a substantial bottleneck to innovation in resonator design.

Optical mode conversion via spatiotemporally modulated atomic susceptibility.

Light is an excellent medium for both classical and quantum information transmission due to its speed, manipulability, and abundant degrees of freedom into which to encode information. Recently, space-division multiplexing has gained attention as a means to substantially increase the rate of information transfer by utilizing sets of infinite-dimensional propagation eigenmodes such as the Laguerre-Gaussian "donut" modes. Encoding in these high-dimensional spaces necessitates devices capable of manipulating photonic degrees of freedom with high efficiency.

Probing gravity by holding atoms for 20 seconds.

Atom interferometers are powerful tools for both measurements in fundamental physics and inertial sensing applications. Their performance, however, has been limited by the available interrogation time of freely falling atoms in a gravitational field. By suspending the spatially separated atomic wave packets in a lattice formed by the mode of an optical cavity, we realize an interrogation time of 20 seconds.

Efficient Adiabatic Spin-Dependent Kicks in an Atom Interferometer.

We present an atom interferometry technique in which the beam splitter is split into two separate operations. A microwave pulse first creates a spin-state superposition, before optical adiabatic passage spatially separates the arms of that superposition. Despite using a thermal atom sample in a small (600  μm) interferometry beam, this procedure delivers an efficiency of 99% per ℏk of momentum separation.

Atom interferometry in an optical cavity.

We propose and demonstrate a new scheme for atom interferometry, using light pulses inside an optical cavity as matter wave beam splitters. The cavity provides power enhancement, spatial filtering, and a precise beam geometry, enabling new techniques such as low power beam splitters (<100  μW), large momentum transfer beam splitters with modest power, or new self-aligned interferometer geometries utilizing the transverse modes of the optical cavity. As a first demonstration, we obtain Ramsey-Raman fringes with >75% contrast and measure the acceleration due to gravity, g, to 60  μg/sqrt[Hz] resolution in a Mach-Zehnder geometry.