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arXiv · 2404.05474

Photon bunching in high-harmonic emission controlled by quantum light

Samuel Lemieux·Sohail A. Jalil·David Purschke·Neda Boroumand·David Villeneuve·Andrei Naumov·Thomas Brabec·Giulio Vampa
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Abstract

Attosecond spectroscopy comprises several techniques to probe matter through electrons and photons. One frontier of attosecond methods is to reveal complex phenomena arising from quantum-mechanical correlations in the matter system, in the photon fields and among them. Recent theories have laid the groundwork for understanding how quantum-optical properties affect high-field photonics, such as strong-field ionization and acceleration of electrons in quantum-optical fields, and how entanglement between the field modes arises during the interaction. Here we demonstrate a new experimental approach that transduces some properties of a quantum-optical state through a strong-field nonlinearity. We perturb high-harmonic emission from a semiconductor with a bright squeezed vacuum field resulting in the emission of sidebands of the high-harmonics with super-Poissonian statistics, indicating that the emitted photons are bunched. Our results suggest that perturbing strong-field dynamics with quantum-optical states is a viable way to coherently control the generation of these states at short wavelengths, such as extreme ultraviolet or soft X-rays. Quantum correlations will be instrumental to advance attosecond spectroscopy and imaging beyond the classical limits.

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Samuel Lemieux, Sohail A. Jalil, David Purschke, Neda Boroumand, David Villeneuve, Andrei Naumov, Thomas Brabec, Giulio Vampa. 2024-04-08. Photon bunching in high-harmonic emission controlled by quantum light. https://arxiv.org/abs/2404.05474

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