We often have internal speakers giving talks at the Atomic, Molecular Optical and Positron Physics (AMOPP) group about their cutting-edge research. Last wednesday (15th February 2017) Professor Sugato Bose presented some of his latest results and calculations based on experiments being performed by  Professor Peter Barker’s group on macroscopic quantum behaviour.

The talk had the broad interest of the department as you can see from the fully-occupied lecture hall above,  and Professor Sugato agreed to provide a copy of his slides, which you can download here, so you may too get an insight into this topic.

 

Abstract:

Probing macroscopic quantum superpositions and the quantum nature of gravity through levitated objects

Prof. Sougato Bose, Dept of Physics & Astronomy University College London

We will discuss theoretical proposals of how quantum superpositions of distinct centre of mass states of a nano-crystal may be created and probed purely by measuring a spin embedded in the object. The idea is to use a levitated diamond with an NV centre spin. Next we will also describe how to reach conditions whereby two such masses interacting purely through gravitational interaction can become entangled. Witnessing such an entanglement experimentally is equivalent to establishing the quantum nature of the gravitational field. Time permitting, we will discuss how the violation of macro-realism can be verified for a levitated nano-object in a loop-hole free manner simply by coarse grained position measurements.