Seminar @ DF-TS - Tue 17 May 2:30 pm - H. Ulbricht - "Prospects to use levitated optomechanics"

[Rosita Glavina - Dip. Fisica UniTS]

We are pleased to announce the next seminar @ DF-Theory Section UniTs:
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H. Ulbricht
University of Southampton, U.K

"Prospects to use levitated optomechanics"

Tuesday, 17 May 2016 - 2:30 pm
Euler Lecture Hall, ICTP Leonardo Building
Strada Costiera, 11

ABSTRACT:
We will discuss ideas to experimentally test collapse models [1] by both 
matter-wave interferometry [2] and non-interferometric methods [3]. 
Testing collapse models intrinsically also means to test the quantum 
superposition principle. Collapse models predict a heating effect, which 
results in a Brownian-like random motion of any isolated particle in 
space. We will emphasise levitated optomechanical systems and discuss 
the possibility to test the heating effect by detecting the motion of 
the particle in position space [4], as well as in the frequency domain 
where the collapse heating effect is theoretical treated as noise in a 
Langevin type approach and predicted to manifest itself as an increase 
of the area of the related power spectral density [3]. We shall also 
explain if gravitation decoherence has strong prospects to be tested 
with levitated optomechanical systems.

We will further discuss some recent ideas to probe the interplay between 
quantum mechanics and gravitation. One idea is to try to directly test 
if gravity is quantum or classical, while a second is to test an effect 
which is predicted for semi-classical gravity (Schrödinger-Newton 
equation)[5], which would allow to experimentally test whether that 
semi-classical approach is valid or not.

We shall also give an update on trapping and cooling experiments of 
levitated optomechanics at Southampton in order to explore the 
experimental feasibility of tests of quantum mechanics and gravitation 
[6]. The overarching goal of our attempts is to build a complete toolbox 
to generate and manipulate Gaussian but also non-Gaussian states, such 
as a spatial superposition state, of the motion of nano- and 
micro-particles in order to realise all possible states of the motional 
dynamics in phase space. This to be done for massive nanoparticles and 
the systematic investigation of noises will further the prospects for 
sensing applications of levitated optomechanics too.

[1] Bassi, A., K. Lochan, S. Satin, T.P. Singh, and H. Ulbricht, Rev. 
Mod. Phys. 85, 471 - 527 (2013),
[2] Bateman, J., S. Nimmrichter, K. Hornberger, and H. Ulbricht, Nat. 
Com. 5, 4788 (2014), Wan, C.,et al ArXiv:1511.02738 (2015).
[3] Bahrami, M., M. Paternostro, A. Bassi, and H. Ulbricht, Phys. Rev. 
Lett. 112, 210404 (2014).
[4] Bera, S., B. Motwani, T.P. Singh, and H. Ulbricht, Sci. Rep. 5, 7664 
(2015).
[5] Grossardt, A., J. Bateman, H. Ulbricht, and A. Bassi, 
arXiv:1510.01696 (2015).
[6] Vovrosh, J., M. Rashid, D. Hempston, J. Bateman, and H. Ulbricht, 
ArXiv:1603.02917 (2016).

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The calendar of events taking place at the Physics Department is 
available at
https://df.units.it/en/events/all_evnt/