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arXiv · 2308.07790

Structured beam controlled super-resolution in quantum dots via rapid adiabatic passage

Partha Das·Samit Kumar Hazra·Tarak Nath Dey
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Abstract

We theoretically investigate rapid adiabatic passage (RAP) based super-resolution microscopy in a two-level quantum dot (QD) system. The system consists of a QD interacting with two structured beams, accompanied by chirping and a time delay. The central concept of this work is inspired by the stimulated emission depletion (STED) microscopy technique. To understand the physical mechanism behind super-resolved spot formation, we employ a variational master equation for the density matrix, incorporating both radiative and non-radiative decay processes. A suitably chosen spatiotemporal envelope of the structured beams enables the formation of a super-resolved image. Unwanted low-intensity circular rings around the focal spot are suppressed using Bessel-modulated truncated structured Laguerre-Gaussian (LG) and super-Gaussian (SG) beams. We also study the temperature dependence of the imaging scheme. The numerical results confirm that at low pulse areas, exciton-phonon coupling distorts the image, whereas at higher pulse areas, exciton-phonon decoupling preserves the image resolution. Hence, the proposed scheme may open up new possibilities for nanoscale imaging and bioimaging applications using QDs.

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Partha Das, Samit Kumar Hazra, Tarak Nath Dey. 2023-08-15. Structured beam controlled super-resolution in quantum dots via rapid adiabatic passage. https://doi.org/10.1088/1367-2630%2Fae5ea0

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