Ultra-strong interaction between light and matter realized.
The interaction between matter and light represents one of the most fundamental processes in physics. Whether a car that heats up like an oven in the summer due to the absorption of light quanta or solar cells that extract electricity from light or light-emitting diodes that convert electricity into light, we encounter the effects of these processes throughout our daily lives. Understanding the interactions between individual light particles – photons – and atoms is crucial for the development of a quantum computer.
Physicists from the Technische Universitaet Muenchen (TUM), the Walther-Meissner-Institute for Low Temperature Research of the Bavarian Academy of Sciences (WMI) and the Augsburg University have now, in collaboration with partners from Spain, realized an ultrastrong interaction between microwave photons and the atoms of a nano-structured circuit.
The measured interaction strength was up to twelve percent of the resonator frequency. This makes it ten times stronger than the effects previously measureable in circuit QED systems and thousands of times stronger than in a true cavity resonator. However, along with their success the researchers also created a new problem: Up to now, the Jaynes-Cummings theory developed in 1963 was able to describe all observed effects very well. Yet, it does not seem to apply to the domain of ultrastrong interactions. "The spectra look like those of a completely new kind of object," says Professor Gross. "The coupling is so strong that the atom-photon pairs must be viewed as a new unit, a kind of molecule comprising one atom and one photon.
Experimental and theoretical physicists will need some time to examine this more closely. However, the new experimental inroads into this domain are already providing researchers with a whole array of new experimental options. The targeted manipulation of such atom-photon pairs could hold the key to quanta-based information processing, the so-called quantum computers that would be vastly superior to today's computers. ###
The research was funded by the Deutsche Forschungsgemeinschaft (DFG) (Cluster of Excellence Nanosystems Initiative Munich and SFB 631), the European Community (EuroSQIP, SOLID), as well as the Spanish Ministry for Science and Innovation.
Contact: Dr. Andreas Battenberg email@example.com 49-892-891-0510 Technische Universitaet Muenchen