Self-Bayesian Aberration Removal via Constraints for Ultracold Atom Microscopy

Abstract

High-resolution imaging of ultracold atoms typically requires custom high numerical aperture (NA) optics, as is the case for quantum gas microscopy. These high NA objectives involve many optical elements each of which contributes to loss and light scattering, making them unsuitable for quantum back-action limited "weak" measurements. We employ a low cost high NA aspheric lens as an objective for a practical and economical-although aberrated-high resolution microscope to image ${}^{87}\mathrm{Rb}$ Bose-Einstein condensates. Here, we present a novel methodology for digitally eliminating the resulting aberrations that is applicable to a wide range of imaging strategies and requires no additional hardware. We recover nearly the full NA of our objective, thereby demonstrating a simple and powerful digital aberration correction method for achieving optimal microscopy of quantum objects. This reconstruction relies on a high quality measure of our imaging system's even-order aberrations from density-density correlations measured with differing degrees of defocus. We demonstrate our aberration compensation technique using phase contrast imaging, a dispersive imaging technique directly applicable to quantum back-action limited measurements. Furthermore, we show that our digital correction technique reduces the contribution of photon shot noise to density-density correlation measurements which would otherwise contaminate the desired quantum projection noise signal in weak measurements.

arXiv comment18 pages, 10 figures

References in corpus (19)

• Theory of Bose-Einstein condensation in trapped gases
• A quantum gas microscope - detecting single atoms in a Hubbard regime optical lattice
• Single-Atom Resolved Fluorescence Imaging of an Atomic Mott Insulator
• SparsePak: A Formatted Fiber Field Unit for The WIYN Telescope Bench Spectrograph. I. Design, Construction, and Calibration
• Watching dark solitons decay into vortex rings in a Bose-Einstein condensate
• Observation of Phase Fluctuations in Bose-Einstein Condensates
• Strong saturation absorption imaging of dense clouds of ultracold atoms
• Bayesian estimation of regularization and PSF parameters for Wiener-Hunt deconvolution
• Extracting density-density correlations from in situ images of atomic quantum gases
• Non-destructive Faraday imaging of dynamically controlled ultracold atoms
• Partial-Transfer Absorption Imaging: A versatile technique for optimal imaging of ultracold gases
• The Planck distribution of phonons in a Bose-Einstein condensate
• Can a Bose gas be saturated?
• Diffraction-contrast imaging of cold atoms
• Revealing buried information: Statistical processing techniques for ultracold gas image analysis
• Non-destructive shadowgraph imaging of ultracold atoms
• Optimally focused cold atom systems obtained using density-density correlations
• Repeated Measurements with Minimally Destructive Partial-Transfer Absorption Imaging
• Multiple-camera defocus imaging of ultracold atomic gases