FOM grants for innovative physics projects involving FELIX

Alexey Kimel and Bas van de Meerakker, physicists at Radboud University, received a total of 800.000 euros from FOM, the Dutch Foundation for Fundamental Research on Matter. Both researchers will use one of the free-electron lasers from the FELIX Laboratory for their innovative proposal in fundamental physics.

Steering quantum spin interactions with light

Alexey Kimel aims to examine new ways of switching magnets with light, a rapidly growing research area of which the outcome may have direct impact on the future development of the 50 billion euro per year data storage industry. To achieve the fastest possible and most efficient magnetization reversal, Kimel aims to employ the strongest interaction in magnetism: the exchange coupling between spins. The effective fields with which the exchange acts on spins can reach 100 to 1000 Tesla and exploiting these huge fields can - in principle - lead to ultrafast changes in the magnetic order. To reach these goals the researchers will employ high magnetic fields from the High Field Magnet Laboratory (HFML), the strength of which is comparable to that of the exchange interaction, and (far)-infrared electromagnetic radiation from the FELIX Laboratory, with photon energies at the scale of the exchange energy.

Molecular billiards in slow motion: when molecules stick together

The study of collisions between individual molecules is one of the most fundamental methods to acquire a detailed understanding of molecular interactions. At low temperatures, the wave-character of atoms and molecules starts dominating their interactions. This leads to exotic quantum phenomena that reveal the fundamental mechanisms of molecular collisions. Recent developments to cool molecules to ever lower temperatures make it possible to study more complex and chemically relevant molecular species. Bas van de Meerakker aims to observe quantum scattering resonances in low-energy collisions between NO and H2, at temperatures as low as 100 mK (-271 °C). At these temperatures, the motion between the colliding molecules is completely quantized, offering unique opportunities to study the evolution of individual partial waves. To achieve this, Van de Meerakker will combine his group’s Stark decelerator with merged beam scattering, velocity map imaging and a free-electron laser from the FELIX Laboratory to prepare quantum states.