MechE Colloquium: Nanotube mechanical resonators – tiny electron forces and large electron backaction
Event details
| Date | 19.10.2021 |
| Hour | 12:15 › 13:15 |
| Speaker | Prof. Adrian Bachtold, Quantum NanoElectronics And NanoMechanics, The Barcelona Institute of Science and Technology (ICFO) |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract:
Mechanical resonators based on carbon nanotubes feature a series of truly exceptional properties. In particular, the mechanical vibrations are highly sensitive to the tiny forces associated with the electron states in the nanotube and vice versa, leading to large backaction effects. In this talk, I will discuss our efforts to cool the amplitude of the thermal vibrations to a few quanta. Cooling is achieved using a simple yet powerful method, which consists in applying a constant (DC) current of electrons through the suspended nanotube in a dilution fridge. I will also present results where we strongly couple mechanical vibrations to the two electron states involved in single-electron tunnelling (SET). It renormalizes the resonance frequency by a large amount, up to 25 % of its value. This results in a highly nonlinear potential for mechanical vibrations despite the relatively low quanta population (about 80 quanta). I will finish the presentation by explaining our effort towards the realization of a mechanical qubit.
Bio:
Adrian Bachtold studied physics at the EPFL and got his PhD from the University of Basel. He is now the principal investigator of the Quantum NanoElectronics & NanoMechanics group at ICFO in Barcelona. His activities focus on the mesoscopic investigation of both quantum electron transport and mechanical resonators. He is APS fellow and is recipient of the CNRS medal and the IBM award of the Swiss Physical Society. He received two ERC grants. Out of the 20 PhD students and postdoc fellows that worked in his group, 13 of them have a permanent position in academic research.
Mechanical resonators based on carbon nanotubes feature a series of truly exceptional properties. In particular, the mechanical vibrations are highly sensitive to the tiny forces associated with the electron states in the nanotube and vice versa, leading to large backaction effects. In this talk, I will discuss our efforts to cool the amplitude of the thermal vibrations to a few quanta. Cooling is achieved using a simple yet powerful method, which consists in applying a constant (DC) current of electrons through the suspended nanotube in a dilution fridge. I will also present results where we strongly couple mechanical vibrations to the two electron states involved in single-electron tunnelling (SET). It renormalizes the resonance frequency by a large amount, up to 25 % of its value. This results in a highly nonlinear potential for mechanical vibrations despite the relatively low quanta population (about 80 quanta). I will finish the presentation by explaining our effort towards the realization of a mechanical qubit.
Bio:
Adrian Bachtold studied physics at the EPFL and got his PhD from the University of Basel. He is now the principal investigator of the Quantum NanoElectronics & NanoMechanics group at ICFO in Barcelona. His activities focus on the mesoscopic investigation of both quantum electron transport and mechanical resonators. He is APS fellow and is recipient of the CNRS medal and the IBM award of the Swiss Physical Society. He received two ERC grants. Out of the 20 PhD students and postdoc fellows that worked in his group, 13 of them have a permanent position in academic research.
Practical information
- General public
- Free