Researchers use non classical light to achieve multi photon electron emission

Strong field quantum optics is a rapidly emerging research topic that integrates nonlinear optoelectronic emission elements rooted in strong field physics with the mature field of quantum optics. Although the distribution of light particles (i.e. photons) has been widely recorded in both classical and non classical light sources, the impact of this distribution on the photoelectric emission process is still poorly understood.

Researchers from Friedrich Alexander University (FAU) in Erlangen Nuremberg and the Max Planck Institute for Photoscience have recently begun exploring the interaction between light and matter through non classical light sources to fill this gap in the literature. Their paper published in the journal Nature Physics suggests that the photon statistics driving the light source are printed on the electron count statistics emitted by metal needle tips, and this observation may have interesting implications for the future development of optical devices.

The co-author and FAU researcher Jonas Heimerl of the paper told Phys.org, "The field of strong field physics has now been highly developed, as evidenced by the Nobel Prize in Physics in 2023." "This physical phenomenon is not limited to atoms, but also occurs on metal surfaces, such as metal needles. A similar and more diverse development is in the field of quantum optics. One aspect of this field is the use of non classical light statistics to generate light, such as bright compressed vacuum."

The main objective of Heimer and his collaborators' latest research is to understand how quantum light originating from non classical light sources interacts with matter. It is worth noting that so far, only classical light sources have been used to explore the interaction between quantum light and matter.

"Our neighbor Professor Maria Chekhova is a world leading expert in the field of bright compressed vacuum generation, a special form of non classical light," co author and FAU researcher Peter Hommelhoff told Phys Org. "Therefore, we collaborated with her and Ido Kaminer, a long-term partner at the Israel Institute of Technology, to study electron emission driven by non classical light."

Heimer, Homerhoff, and their research team at FAU collaborated closely with researcher Chekhova, who has extensive expertise in the field of quantum optics, to conduct experiments. Chekhova is known for her work in the generation of bright compressed vacuum, which requires the use of nonlinear optical processes to generate bright compressed vacuum (a type of non classical light).

"In our experiment, we used this non classical light source to trigger the photoelectric emission process of a metal needle tip with a size of only a few tens of nanometers," explained Heimer. "It can be regarded as Einstein's famous photoelectric effect, but modern light sources exhibit extreme intensity and fluctuations within each laser pulse."

For each laser pulse generated, researchers calculated the number of electrons in both classical and non classical light sources. Interestingly, they found that the number of electrons can be directly influenced by the driving light.

"Our findings may be of great interest to people, especially for electronic imaging applications such as biomolecular imaging," said Heimer
As is well known, biomolecules are highly susceptible to damage, and reducing the electron dose used for imaging these molecules can reduce the risk of such damage. Heimerl et al.'s paper. It is possible to modulate the number of electrons to meet the specific application requirements.
"However, before we can solve this problem, we must prove that we can also imprint another type of photon distribution on electrons, which is the photon distribution with reduced noise, but this may be difficult to achieve," said Homelhoff.

The discovery of this latest work may soon bring new opportunities for the study of strong field quantum optics. Meanwhile, they can serve as the foundation for new devices, including sensors and strong field optical devices that utilize the interaction between quantum light and electrons.

Source: Laser Net