Image generated with Chat-GPT using the prompt „Create a picture of a satellite in earth orbit connected via a laser beam to a ground station. There is a quantum memory on the satellite as well as on the ground station. They are in an entangled quantum state.“ Copyright: Dennis Rätzel / ZARM, University of Bremen

Photons and quantum memories in the Earth's gravitational field

Special experiments are needed to investigate the interplay between quantum physics and the theory of gravity, one of the great mysteries of physics. Researchers at the ZARM (Center of Applied Space Technology and Microgravity) at the University of Bremen have presented a new experimental approach in the journal "Quantum". This approach investigates how gravity affects the building blocks of quantum systems.

In the field of space technology, where these tiny building blocks are produced in the form of light particles and transmitted over long distances through the Earth's gravitational field, it is particularly important to understand the effects of gravity. An interesting phenomenon in this context is the emergence of a special connection between the movement of a quantum system and its internal energy structure, also known as entanglement, in a gravitational field. This connection results from the "time dilation" or "redshift", known from the theory of gravity, which arises between two physical systems when they move at different speeds or at different heights in the Earth's gravitational field. Investigations into this behavior are already taking place in various fields, including atomic physics, physics of light particles and sound waves in quantum states.

The research team has analyzed this connection between motion and internal energy structure in experiments with light particles and quantum memories. They present a practical experimental setup and a study that shows how these effects can be observed on smaller scales than previously proposed. Such an experiment would help to test theoretical models and link the effects of quantum physics to gravitational theory. The article in "Quantum" also provides the first detailed investigation of how gravity affects quantum memories in space, which could be very important for future quantum-based global communication networks.

The publication was written in collaboration with researchers from the Institute of Physics and IRIS Adlershof at Humboldt-Universität zu Berlin and the Ferdinand-Braun-Institut.

Link to the publication: doi.org/10.22331/q-2024-02-29-1273


Scientific contact:

Dr Dennis Rätzel
0421 218-57935 

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Jasmin Plättner
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