Long-Baseline Universal Matter-wave interferometry

Stefan Gerlich, University of Vienna

In recent years there has been a growing experimental effort to create and investigate highly macroscopic quantum states. Matter-wave interferometers of the Talbot-Lau type have proven to be particularly suited for the exploration of the quantum nature of massive particles.

We here report on the completion a near-field matter-wave interferometer of the newest generation. At a baseline of two meters, the new Viennese Long-baseline Universal Matter-wave Interferometer(LUMI) outperforms its predecessor by one order of magnitude with regard to the accessible mass regime and by a factor 100 in force sensitivity. LUMI will be able to operate with de Broglie wavelengths of less than 50 fm. This will make it possible to study the quantum superposition of particles in the range of 100,000 amu and to thus set stricter bounds for potential modifications of quantum theory such as objective collapse models.

LUMI is sensitive to external forces as small as 10^-26N. This puts high experimental demands on the vibration insulation and even necessitates compensation of the Coriolis force but also makes LUMI and ideal platform for precision metrology experiments. LUMI offers the option to switch between different diffraction mechanisms and is thus suited for complex organic molecules and metal clusters as well as for single atoms. The modular design of the interferometer also allows for the introduction of electric and magnetic fields, collision cells and spectroscopy lasers. This makes it possible to explore the electronic, optical and magnetic and through these also the structural properties of a large and diverse class of particles with high precision in free flight.

I will present the very first experimental results of our new device and provide an overview of its future prospects.