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ANDREAS LYRAS

Associate Professor

FACULTY, DEPARTMENT OF PHYSICS and ASTRONOMY

كلية العلوم
Department Of Physics & Astronomy
publication
Journal Article
2020

A Novel Metal nanoparticle-Graphene nanodisk-Quantum dot Hybrid-System-based spaser

Alsalhi, M. Tohari, A. Lyras, and M. . 2020

Active nanoplasmonics have recently led to the emergence of many promising applications. One of them is the spaser (surface plasmons amplification by stimulated emission of radiation) that has been shown to generate coherent and intense fields of selected surface plasmon modes that are strongly localized in the nanoscale. We propose a novel nanospaser composed of a metal nanoparticles-graphene nanodisks hybrid plasmonic system as its resonator and a quantum dots cascade stack as its gain medium. We derive the plasmonic fields induced by pulsed excitation through the use of the effective medium theory. Based on the density matrix approach and by solving the Lindblad quantum master equation, we analyze the ultrafast dynamics of the spaser associated with coherent amplified plasmonic fields. The intensity of the plasmonic field is significantly affected by the width of the metallic contact and the time duration of the laser pulse used to launch the surface plasmons. The proposed nanospaser shows an extremely low spasing threshold and operates in the mid-infrared region that has received much attention due to its wide biomedical, chemical and telecommunication applications

Publication Work Type
Research article
Volume Number
10
Issue Number
3
Magazine \ Newspaper
Nanomaterials
Pages
416 to 432
more of publication
publications

We present the theoretical framework and the approximations needed to numerically simulate the response of alkali metal atoms under multi-photon excitation.

by N Merlemis, A Lyras, G Papademetriou, D Pentaris, T Efthimiopoulos
2022
Published in:
SPRINGER
publications

We report theoretical results for the transition amplitudes of two-photon transitions induced in a one-active-electron atomic system by a LG10 beam. We identify the excitation pathways for…

by A Al-Khateeb, A Lyras, V E Lembessis, O M Aldossary
2022
Published in:
ELSEVIER
publications

We investigate the quantized states of a two-level Rb atom that is trapped by the optical dipole potential when the atom interacts with a helical optical tube light field.

by Vassilis E. Lembessis, Andreas Lyras, and Omar M. Aldossary
2022
Published in:
OPTICA