Matter-Waves in Dynamic Wave-Guides

by Prof. Wolf Von Klitzing

Institute of Electronic Structure and Laser, Heraklion

at Quantum optics seminar

Wed, 01 Dec 2021, 15:00
ZOOM only

Abstract

Zoom link: https://us02web.zoom.us/j/81826440261

Abstract:
Matterwaves are in many ways equivalent to photonic waves, with the exceptions that their fundamental constituents carry mass. This makes them extremely promising candidates for sensing, especially gravity. The most recent proposals and projects include space borne gravity sensing of its mass distribution, gravitational wave sensing and dark matter detection. Unfortunately, such extreme measurements warrant extreme measures, i.e. extremely large experiments (up to 100m tall vacuum chambers) or specialized satellites in zero gravity. Therefore, one of the aims of the field of ultra-cold atoms has been since many years to confine and manipulate atomic waves in time-changeable traps and waveguides. This has been done in a number of research groups using optical or magnetic potentials [1].

We have recently a novel class of trapping potentials based on the time-averaging of adiabatic magnetic potentials (TAAP) and demonstrated that we can construct coherent matterwave guides that can transmit atoms over macroscopic distances (40cm) without decohering their internal or external quantum states [2]. Using optimal control theory we accelerate the atom clouds with minimal heating up to 40 times their velocity of sound. In order to manipulate the matterwaves, we have developed a magnetogravitational matter-wave lenses as a novel tool in atom-optics in atomtronic waveguides. We collimate and focus matter waves originating from Bose-Einstein condensates and ultracold thermal atoms in ring-shaped time-averaged adiabatic potentials. We demonstrate ``delta-kick cooling'' of Bose-Einstein condensates, reducing their expansion energies by a factor of 46 down to 800 pK [3]. The atomtronic waveguide ring has a diameter of less than one millimeter, compared to other state- of-the-art experiments requiring zero gravity or free-flight distances of ten meters and more. This level of control with extremely reduced spatial requirements is an important step toward atomtronic quantum sensors.

[1] The Ben-Gurion University is at the Avant-Guard for the microchip-based manipulation of atoms (atomchips).
[2] Saurabh Pandey, Hector Mas, Giannis Drougakis, Premjith Thekkeppatt, Vasiliki Bolpasi, Georgios Vasilakis, Konstantinos Poulios, and Wolf von Klitzing Hypersonic Bose--Einstein condensates in accelerator rings, Nature 570:7760 205--209 (2019)
[3] Saurabh Pandey et al. Atomtronic Matter-Wave Lensing Phys. Rev. Lett. 126, 17 (2021)

Created on 29-11-2021 by Folman, Ron (folman)
Updaded on 29-11-2021 by Folman, Ron (folman)