Etienne Wamba, Dr.
Lecturer in Physics
University of Buea
from April to June 2022
Born in 1980 in Baleveng, Cameroon
Studied Physics at the University of Dschang and Mechanics at the University of Yaounde 1
Fellowship
Iso Lomso-Fellow
Project
Splitting Dynamics of Quantum Gases
Since the realization of the first Bose-Einstein condensate a couple of decades ago, there has been intense work in the quantum gas field. Bose-Einstein condensates constitute a very interesting platform for highly controllable experiments aiming mostly at unravelling the quantum properties of matter on a large scale. Experiments with Bose-Einstein condensates also allow us to mimic the behavior of physical systems that cannot be directly explored. With the advent of the era of high-frequency and big-data processing, the hunt for better crypto-machines, miniaturized devices, and more powerful computers has heightened interest in quantum mechanics and in particular in Bose-Einstein condensates. The complete characterization of the devices with dominant quantum effects will have to take into account various kinds of quantum dynamics that could take place inside them. In this respect, the present project is devoted to examining the splitting dynamics of ultra-cold quantum gases using analytical and numerical tools. More specifically, we address a crucial aspect of quench physics in the simple scenario of a quantum gas being spatially split by deforming its trapping potential from single-well into double-well form. The interaction between the particles of the gas varies along with the trap splitting. The system in consideration is realistic and can be achieved experimentally. However, we will use an exact space-time mapping to investigate the system. We intend to show that the time evolution of such model many-body systems with rapid parametric driving may have a kind of hidden adiabaticity, inasmuch as the quench-like scenarios of rapid splitting can be mapped exactly onto much slower adiabatic splitting in which excitations are negligible. Applying the mapping in a mean-field regime, we will examine how different dynamical mechanisms of non-equilibrium excitation can compete or cooperate. These results may allow improvements to general theories of non-equilibrium evolution, to avoid an intuitively wrong estimation of excitations.Recommended Reading
Wamba, Etienne, Alidou Mohamadou, and Timoléon C. Kofané (2008). "Modulational Instability of a Trapped Bose-Einstein Condensate with Two- and Three-Body Interactions." Physical Review E 77: 046216. https://doi.org/10.1103/PhysRevE.77.046216.
Wamba, Etienne, Axel Pelster, and James R. Anglin (2016). "Exact Quantum Field Mappings between Different Experiments on Quantum Gases." Physical Review A 94: 043628. https://doi.org/10.1103/PhysRevA.94.043628.
Tamilthiruvalluvar, Ramakrishnan, Etienne Wamba, Sabari Subramaniyan, and Kuppuswamy Porsezian (2019). "Impact of Higher-Order Nonlinearity on Modulational Instability in Two-Component Bose-Einstein Condensates." Physical Review E 99: 032202. https://doi.org/10.1103/PhysRevE.99.032202.
Publications from the Fellows' Library
Wamba, Etienne (Woodbury, NY, 2019)
Wamba, Etienne (Woodbury, NY, 2016)
Exact quantum field mappings between different experiments on quantum gases
Wamba, Etienne (Woodbury, NY, 2008)
Modulational instability of a trapped Bose-Einstein condensate with two- and three-body interactions
