Research - Stochastic and Quantum Thermodynamics

Optical control of nano- and microparticles has recently found application in two relatively young fields of physics: Stochastic Thermodynamics and Quantum Optomechanics. In the former case, optical tweezers were used to control colloidal particles in liquid, to test new theoretical predictions and to realize novel concepts, like a stochastic heat engine. In Quantum Optomechanics, the combination of optically levitation with cavity optomechanical control has been proposed as a new paradigm system for fundamental tests of quantum theory. In this direction, we have recently been able to demonstrate cavity cooling of levitating nanoparticles taking an important step towards such experiments.

The idea behind this project is to enhance cross-fertilization between those flourishing and highly related fields by exploiting all-optical control of levitated nanoobjects as a common experimental theme that allows access to the quantum regime.

The central goal is to provide a testbed of unique flexibility for stochastic thermodynamics in the classical and in the quantum regime and to implement and characterize new concepts of quantum thermodynamics like quantum heat engines.

To achieve this, we will build on the technology existing for optical tweezers in liquid and implement complex optical potential landscapes in vacuum. This will enable a great level of control over the dynamics of a levitated nanoparticle. We further continue to fully develop levitating cavity optomechanics to additionally implement time-dependent anisotropic friction and/or temperature and to enable preparation of non-classical states and quantum state analysis. Combining these experiments in a single setup allows to implement thermodynamic processes with an extraordinary level of control and to implement completely new tests of thermodynamics with an unprecedented degree of generality. Even more, it may allow to enter a regime where the validity of general theorems has not been shown theoretically to date.

The major impact of such a new scientific tool surely is its value for understanding fundamental questions in thermodynamics, statistical physics and the foundations of quantum physics and as a model for new thermodynamic heat engines. In addition, however, optically levitating nanospheres in ultra-high vacuum have also been anticipated to serve as excellent sensors of force and mass and might therefore also find a direct way towards technological application.

Research on levitated optomechanics

If you are interested in our other projects on levitated optomechanics, please visit the Aspelmeyer group page Quantum Controlling Levitated Systems.

Our research is supported by: