"Experiments to Probe Quantum Linearity with Massive Nanoparticles" Markus Arndt

Speaker

Markus Arndt, Professor, University of Vienna, Austria

Abstract

Quantum physics is the best-confirmed theory of nature, and yet important questions have remained open: Why do we find unitary evolution in quantum mechanics but not in the macroscopic world we live in? What defines the cut between coherent superpositions of quantum states and seemingly irreversible measurements among many mutually exclusive possibilities? These questions have been guiding our research on nanoparticle interferometer and control schemes1. We were able to demonstrate the quantum wave nature of fullerenes, vitamins2, polypeptide antibiotics and macromolecules up to 10’000 amu3, and in all experiments so far, quantum mechanics was confirmed and clearly distinct from a classical world view. In an ongoing effort to prepare novel quantum experiments between 104 – 106 amu we have established a new long-baseline matter-wave interferometer that can cope with de Broglie wavelengths even below 100 fm. In an effort to push the mass limit by even another two orders of magnitude, to between 106-108 amu, we are advancing nanoparticle cavity optomechanics. This includes methods to launch and detect high-mass silicon nanorods4 and new microcavities5, 6 that strongly couple these nanoparticles to intense light fields. The combination shall enable cooling to 5D quantum states, for novel tests at the quantum-classical interface7.

1. Arndt M, Hornberger K. Insight review: Testing the limits of quantum mechanical superpositions. Nature Phys 10, 271-277 (2014).
2. Mairhofer L, Eibenberger S, Cotter JP, Romirer M, Shayeghi A, Arndt M. Quantum-assisted metrology of neutral vitamins in the gas phase. Angew Chem Int Ed 56, 10947 - 10951 (2017).
3. Eibenberger S, Gerlich S, Arndt M, Mayor M, Tüxen J. Matter-wave interference of particles selected from a molecular library with masses exceeding 10 000 amu. Phys Chem Chem Phys 15, 14696 - 14700 (2013).
4. Asenbaum P, Kuhn S, Nimmrichter S, Sezer U, Arndt M. Cavity cooling of free silicon nanoparticles in high-vacuum Nature Communications 4, 2743 (2013).
5. Stickler BA, Nimmrichter S, Martinetz L, Kuhn S, Arndt M, Hornberger K. Rotranslational cavity cooling of dielectric rods and disks. Phys Rev A 94, 033818 (2016).
6. Kuhn S, et al. Cavity-assisted manipulation of freely rotating silicon nanorods in high vacuum. Nano Lett 15, 5604−5608 (2015).
7. Stickler BA, Papendell B, Kuhn S, Millen J, Arndt M, Hornberger K. Orientational quantum revivals of nanoscale rotors. arXiv:180301778v1 (2018).

This is a part of the summer school CQD2018 hosted by Nic Chormaic Unit & Busch Unit.
Looking forward to seeing mane of you at the seminar.

Okinawa School in Physics 2018: Coherent Quantum Dynamics (CQD)