Kavli Affiliate: Giorgio Gratta
| First 5 Authors: Charles P. Blakemore, Denzal Martin, Alexander Fieguth, Nadav Priel, Gautam Venugopalan
| Summary:
Librational motion, whereby a rigid body undergoes angular oscillation around
a preferred direction, can be observed in optically trapped, silica
microspheres. We demonstrate the cooling of one librational degree of freedom
for $sim 5~mu$m diameter spheres that have been induced to rotate with an
external electric field coupled to their electric dipole moment. Cooling is
accomplished by adding a phase modulation to the rotating field. The degree of
cooling is quantified by applying a $pi/2$ shift to the phase of the electric
field and fitting the resulting exponential decay of the librational motion to
obtain a damping time, as well as estimating a mode temperature from the
observed libration in equilibrium. The result is an important step in the study
of the dynamics of trapped microspheres, crucial to cooling the mechanical
motion to its ground state, as well as providing insights regarding the charge
mobility in the material at microscopic scales.
| Search Query: ArXiv Query: search_query=au:”Giorgio Gratta”&id_list=&start=0&max_results=3