Low-frequency spectroscopy for quantum multilevel systems
ORAL
Abstract
A periodically driven quantum system with avoided-level crossing experiences both nonadiabatic transitions and wave-function phase changes. These result in coherent interference fringes in the system’s occupation probabilities. For qubits, with repelling energy levels, such interference, named after Landau-Zener-Stückelberg-Majorana, displays arc-shaped resonance lines. In the case of a multilevel system with an avoided-level crossing of the two lower levels, we demonstrate that the shape of the resonances can change from convex arcs to concave heart-shaped and harp-shaped resonance lines. Indeed, the whole energy spectrum determines the shape of such resonance fringes and this also provides insight into the slow-frequency system spectroscopy. As a particular example, we consider this for valley-orbit silicon quantum dots, which are important for the emerging field of valleytronics.
[1] A. I. Ryzhov, S. N. Shevchenko, F. Nori, Phys. Rev. B 98, 195434 (2018).
[1] A. I. Ryzhov, S. N. Shevchenko, F. Nori, Phys. Rev. B 98, 195434 (2018).
*This work was supported by the ARO, JSPS, JST, MEXT, NTT, AFOSR, AOARD, FQXi.
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Presenters
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Artem Ryzhov
- ILTPE, Ukraine