Matter-wave Optics

Within this area, the Theoretical Quantum Optics group is dedicated to the description of the dynamics of quantum gases. Not only the effective nonlinear dynamics within the framework of a mean-field approximation is of interest, but also atom-light and atom-atom interactions. Such interactions, although difficult to control, can each serve as resources to generate particularly sensitive but also difficile quantum states. Just as optical quantum states can increase the sensitivity of gravitational wave antennas, comparable states of quantum gases can be used to enable and study the operation of atom interferometers in new regimes.

In addition to these nonlinear aspects of many-body systems, novel scattering mechanisms induced by optical lattices in unusual configurates are developed and simulated in this area of research. Such approaches offer new possibilities for sensors that are simultaneously sensitive to accelerations in different spatial directions, opening the door to multidimensional inertial sensing.

To extend interrogation times of atom interferometers in earthbound setups and thereby increase their sensitivity, levitated, semi-guided, or guided geometries represent a promising approach. Such a configuration leads to a very different dynamics of quantum gases within waveguides compared to free fall, whose effects are studied and estimated. In addition, it is possible to introduced potential barriers that act as beam splitters, resonators and cavities based on quantum tunneling.

As a further point, the group studies the quantum dynamics of relativistic electrons in periodic light fields and explores their feasibility as new sources of radiation.

S. Hartmann, J. Jenewein, E. Giese, S. Abend, A. Roura, E. M. Rasel & W. P. Schleich
Regimes of atomic diffraction: Raman versus Bragg diffraction in retroreflective geometries
Physical Review A 101, 053610 (2020)
H. Ahlers, H. Müntinga, A. Wenzlawski, M. Krutzik, G. Tackmann, S. Abend, N. Gaaloul, E. Giese, A. Roura, R. Kuhl, C. Lämmerzahl, A. Peters, P. Windpassinger, K. Sengstock, W. P. Schleich, W. Ertmer & E. M. Rasel
Double Bragg interferometry
Physical Review Letters 116, 173601 (2016)
P. Berg, S. Abend, G. Tackmann, C. Schubert, E. Giese, W. P. Schleich, F. A. Narducci, W. Ertmer & E. M. Rasel
Composite-Light-Pulse Technique for High-Precision Atom Interferometry
Physical Review Letters 114, 063002 (2015)
E. Giese, A. Roura, G. Tackmann, E. M. Rasel & W. P. Schleich
Double Bragg diffraction: A tool for atom optics
Physical Review A 88, 053608 (2013)