UNO, the Ultrafast Nonlinear Optics Lab

Our sight, a magnifying lens, a telescope, a camera: we all experience the unique role of light in the discovery of the world around us. Light, not only reveals the world but also shapes it, interacting with matter in many ways: from the warmth of lying in the sun to the creation of particles from the vacuum. Optics deals with the physics of light and its interactions with matter.

When light is intense as in the focus of a lens, it interacts strongly with matter and gives rise to several intriguing effects. For instance, two light rays may stop ignoring each other, and combine to produce new beams that were not present before, like in Star Wars' Death Star. This interaction regime is called nonlinear and is at the core of UNO.

A magnifying lens concentrates the light power in a tiny spot increasing its intensity, the quantity ultimately responsible for the onset of the nonlinear regime. Very similarly, we can concentrate the light energy in short bursts of radiation to further increase the intensity. Short pulses of less than 100 femtoseconds (hence the name ultrafast), are routinely used by UNO’s users to test how intense light modifies matter and gives rise to unexpected effects.

Not only nonlinear interactions produce novel beams, but also enable to change the light colours, or more specifically, its frequency. UNO team is devoted to studying and optimising the frequency conversion in different nonlinear regimes, both to produce and detect radiation hardly accessible by the available means and to push the boundaries of nonlinear optics into unexplored regions of the electromagnetic spectrum.

UNO targets two main themes

Mid-infrared and Terahertz optics. The generation, detection, imaging and applications of long-wavelength radiation.

Quantum optics. The possibilities provided by non-classical states of light for enhancing light detection and imaging.

Combining the PI's experience in these two research areas led to the ideaof employing non-classical states of light to improve the detection of terahertz fields. This research activity is currently funded by the EPSRC grant "Quantum-enhanced THz spectroscopy and imaging" (EP/P009697/1).

Quantum optics is typically limited to the visible or near-infrared frequencies. UNO aims at expanding its reach where a significant part of cutting-edge photonics research is now focused: the long- wavelength part of the spectrum. To achieve this goal, we shall depart from the standard photon measurement approach, and we aim at developing a new set of quantum technologies based on time-resolved electric field measurements.