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arXiv · 2305.02904

Quantum Enhanced Probes of Magnetic Circular Dichroism

Chengyun Hua·Claire E. Marvinney·Seongjin Hong·Matthew Feldman·Yun-Yi Pai·Michael Chilcote·Joshua Rabinowitz·Raphael C. Pooser·Alberto Marino·Benjamin J. Lawrie
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Abstract

Magneto-optical microscopies, including optical measurements of magnetic circular dichroism, are increasingly ubiquitous tools for probing spin-orbit coupling, charge-carrier g-factors, and chiral excitations in matter, but the minimum detectable signal in classical magnetic circular dichroism measurements is fundamentally limited by the shot-noise limit of the optical readout field. Here, we use a two-mode squeezed light source to improve the minimum detectable signal in magnetic circular dichroism measurements by 3 dB compared with state-of-the-art classical measurements, even with relatively lossy samples like terbium gallium garnet. We also identify additional opportunities for improvement in quantum-enhanced magneto-optical microscopies, and we demonstrate the importance of these approaches for environmentally sensitive materials and for low temperature measurements where increased optical power can introduce unacceptable thermal perturbations.

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Chengyun Hua, Claire E. Marvinney, Seongjin Hong, Matthew Feldman, Yun-Yi Pai, Michael Chilcote, Joshua Rabinowitz, Raphael C. Pooser, Alberto Marino, Benjamin J. Lawrie. 2023-05-04. Quantum Enhanced Probes of Magnetic Circular Dichroism. https://arxiv.org/abs/2305.02904

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