Lasers, experiments and ice flowers – Girls' Day at MPQ

A day of quantum optics, science and discovery for fifteen girls at MPQ.

At the nationwide Girls’Day, girls have the chance to explore careers where women are still underrepresented. The Max Planck Institute of Quantum Optics has been part of the initiative for many years, and once again this year, the participants enjoyed a wide-ranging programme. Through talks, hands-on experiments and tours of a lab and the mechanical workshop, they gained insight into the diverse everyday work of a quantum optics researcher.

As every year, the Girls’Day participants were welcomed with a wide-ranging programme. One key element: the laser – arguably the most important tool in the intitute’s research. “Quantum optics is the study of the world using laser light,” explained Dr Silke Stähler-Schöpf, head of the MPQ’s PhotonLab, during her introductory talk.

What that looks like in practice was demonstrated by doctoral student Carlotta Versmold. In her lab, she showed the students how she works with an interferometer and laser light in the infrared range – with a wavelength of 810 nanometres, invisible to the human eye. The students were all the more amazed when a special camera revealed the interference pattern on a screen.

But precision is not only vital in research – it also plays a key role in the insitute’s own mechanical workshop. This is where custom-made components for the labs are produced. Industrial mechanic Anton Pittner gave a tour of the workshop and explained how CNC, turning and milling machines operate at a precision of one hundredth of a millimetre. Even tiny differences in hair thickness matter here, as he pointed out.

One of the highlights of the day was lunch – with pizza, frozen yoghurt, fresh berries and a special treat: the PhotonLab’s liquid nitrogen train. But what truly captured everyone’s attention were the roses. The students dipped pale pink flowers into liquid nitrogen and then shattered them like glass. “It breaks just like glass – only glass is a bit heavier,” one student remarked. Surprisingly, even after their nitrogen bath, the roses retained their scent.

Whether indoors or out, this day was all about exploring, experimenting and discovering. And the next Girls’Day is already on the calendar: Thursday, 23 April 2026!