Periodically driven three-level systems
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2016-09-01 |
| Journal | Physical review. B./Physical review. B |
| Authors | M. B. Kenmoe, Lukong Cornelius Fai |
| Institutions | UniversitƩ de Dschang |
| Citations | 18 |
Abstract
Section titled āAbstractāWe study the dynamics of a three-level system (ThLS) sinusoidally driven in\nboth longitudinal and transverse directions and in the presence of a uniaxial\nanisotropy $D$ entering the generic Hamiltonian through the zero-energy\nsplitting term $D(S^{z})^{2}$ where $S^{z}$ is the projection of the spin\nvector along the quantization direction. As a consequence of the addition of\nthis term, the order of the symmetry group of the Hamiltonian is increased by a\nunit and we observe a sequence of cascaded $SU(3)$\nLandau-Zener-St\āuckelberg-Majorana (LZSM) interferometers. The study is\ncarried out by analytically and numerically calculating the probabilities of\nnon-adiabatic and adiabatic evolutions. For non-adiabatic evolutions, two main\napproximations based on the weak and strong driving limits are discussed by\ncomparing the characteristic frequency of the longitudinal drive with the\namplitudes of driven fields. For each of the cases discussed, our analytical\nresults quite well reproduce the gross temporal profile of the exact numerical\nprobabilities. This allows us to check the range of validity of analytical\nresults and confirm our assumptions. For adiabatic evolutions, a general theory\nis constructed allowing for the description of adiabatic passages in arbitrary\nThLSs in which direct transitions between states with extremal spin projections\nare forbidden. A compact formula for adiabatic evolutions is derived and\nnumerically tested for some illustrative cases. Interference patterns\ndemonstrating multiple LZSM transitions are reported. Applications of our\nresults to the Nitrogen Vacancy Center (NVC) in diamond are discussed.\n