The 3DQ Microscope: A Novel System Using Entangled Photons to Generate Volumetric Fluorescence and Scattering Images for Bioenergy Applications

Authors:

Audrey Eshun¹* ([email protected]), Dominique Davenport¹, Brandon Demory¹, Paul Mos², Yang Lin², Sam Jeppson¹, Ashleigh Wilson¹, Shervin Kiannejad¹, Tiziana Bond¹, Mike Rushford¹, Chuck Boley¹, Edoardo Charbon², Claudio Bruschini², Ted Laurence¹(PI)

Institutions:

¹Lawrence Livermore National Laboratory^{; 2}École Polytechnique Fédérale de Lausanne

Abstract

In the study of biological systems, real-time 3D microscopy is an important tool in understanding how live cells move and interact with other cells, microbes, and other external elements. Although these dynamics can currently be studied with confocal and light sheet microscopy, for example, these approaches require scanning either the beam or the sample, exposing the sample to higher excitation energies and limiting time resolution of the imaging process.

An alternative approach that is ideal for dynamic information is to simultaneously capture the scene from two perspectives. This limits the time resolution only by the acquisition rate of each sensor. However, recreating the 3D scene from two views requires correlating features in both views, posing challenges at higher densities. This study proposes that quantum-entangled light can provide the 3D information using a new detection architecture while keeping peak excitation intensity low to preserve the integrity of the sample and avoiding biases that can be caused by scanning. Quantum-entangled light can be spatially separated while preserving the momenta and temporal relations of entangled photons.

Utilizing quantum-entangled light generated by a beta barium borate crystal and the concepts of quantum ghost imaging, the team presents a microscope that views microscopic specimens in 3D from a single snapshot. This is achieved by utilizing two event-based 2D sensors in which information is relayed, through correlations, to generate two perspectives from a single scene. The quantum-entangled light source allows researchers to correlate signal and idler, both spatially and temporally. Group members characterize the microscope by imaging resolution targets at various depths, using models to guide them in the optimization of the crystal orientation, and attempt to understand the achievable depth of field with the specific light source.

After characterization, researchers image gold nanoclusters with the ghost imaging microscope. Additionally, the team presents its first use of utilizing scattering correlations with the 3DQ microscope for the imaging of nanoparticles. This group foresees a large potential for the 3DQ microscope in various areas, including measuring the dynamics of microbial symbiosis in bioenergy algal ponds and plants. More broadly, the 3DQ concept can be applied to many biological systems and extended to longer wavelength and spectroscopy applications requiring more dimensions of information while retaining high resolution and sensitivity.

Image

Simplified Ghost Image Setup. showing the direct signal image and the ghost image obtained after coincidence filtering. [Courtesy Lawrence Livermore National Laboratory]

Funding Information

This work was performed under the auspices of DOE by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.