Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Nonlinear Optical Physics & Materials

AMPLIFICATION WITHOUT INVERSION IN SEMICONDUCTOR QUANTUM DOT

A. Hajibadali, Karim Abbasian, Ali Rostami

Published Mar 1, 2011• 0 citations
Publisher

Abstract

In this paper, we have realized amplification without inversion (AWI) in quantum dot (QD). A Y-type four-level system of InxGa1-xN quantum dot has been obtained and investigated for AWI. It has been shown that, with proper setting of control fields' amplitude, we can obtain reasonable gain. With proper setting of phase difference of control fields and probe field, we can obtain considerable gain in resonant wavelength. We have designed this system by solving the Schrödinger–Poisson equations for InxGa1-xN quantum dot in GaN substrate, self-consistently.

DOI
10.1142/s0218863511005929

Related papers

Amplification of light in In x Ga 1-x N/GaN semiconductor quantum dot without high intensity control fields

A. Soltany, A. Hajibadali, A. Soltani +2 more

This study aims to designing quantum dot semiconductor optical amplifier (QD-SOA) by amplification without inversion technique in InxGa1-xN/GaN semiconductor quantum dot (nanostructure). To do this, eigen energies and their corresponding wave functions of a Y-type four-level atomic system were obtained by solving of Schrodinger- Poisson equations self-consistently (considering intersublevel transitions) in InxGa1-xN/GaN quantum dot. The principle of quantum optics to obtain dynamic property of quantum dot density matrix elements was employed and investigated the lasing without inversion (LWI) phenomenon in this quantum dot.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 29, 2010•0 citations

Enhancement of refractive index with amplification in an InGaN/GaN quantum dot nanostructure

M. Jamshidnejad, Majid Vaezzadeh, HAMID RAHIMPOUR SOLEIMANI +1 more

Abstract In this letter, we investigated the behaviors of the absorptive–dispersive properties of weak probe light in a four-level InGaN/GaN quantum dot nanostructure. In order to achieve the wave functions and their corresponding energy levels of the mentioned quantum dot nanostructure, Schrödinger and Poisson equations must be solved self consistently for carriers (here electrons) in quantum dots. The enhanced refractive index with amplification can be obtained via adjusting the corresponding controllable parameters such as intensity, detuning and relative phase of the applied fields. Our proposed scheme provides a realistic model for controlling the index of refraction in a quantum dot nanostructure.

Laser Physics Letters•Mar 4, 2016•18 citations

Phase control of group velocity of light in an InGaN/GaN quantum dot nanostructure

Hossein Jafarzadeh, Elnaz Ahmadi Sangachin, Seyyed Hossein Asadpour

By solving self-consistently Schrödinger – Poisson equations for a carrier in the conduction band of an InGaN/GaN quantum dot, a four-level quantum system is described. It is found that in the presence of terahertz signal radiation, the medium becomes phase dependent, which ensures the phase control of the group velocity of a weak probe pulse from slow to fast light.

Quantum Electronics•Sep 28, 2015•1 citation

Quantum interference effects on the probe amplification without and with inversion in a four-level system

Bing Zhang, Weihua Xu, Zhang Hui-Fang +1 more

A four-level system driven by two coherent fields is considered. It is shown that in the presence of an incoherent pump, the probe gain at a short wavelength can be achieved due to the quantum interference. Our density matrix calculation provides the conditions for probe amplification from different origins, including gain without population inversion on any state basis, gain with population inversion on the dressed-state basis and gain with population inversion on the bare-state basis. Also, by controlling the Rabi frequency of the coupling field a total change from non-inversion to inversion can be achieved which does not depend on the intensity of the incoherent pump.

Chinese Physics•Sep 28, 2004•4 citations

Anomalous dispersion via coherent field in an InGaN/GaN quantum dot nanostructure

Ghahraman Solookinejad, M. Panahi, Elnaz Ahmadi Sangachin +1 more

The dispersion behaviors of weak probe light in an InGaN/GaN quantum dot (QD) nanostructure driven by a coherent coupling field is investigated. InGaN/GaN QD nanostructure is designed numerically by solving the Schrödinger–Poisson coupled equations. By specific values of QD radius, an appropriate four-level QD nanostructure which is suitable for interaction by a weak probe light and a coherent coupling field is designed. It is shown that switching from normal to anomalous dispersion can be achieved by the intensity of coupling field. Therefore, fast light propagation in this model can be obtained by reduced absorption.

Modern Physics Letters B•Jan 22, 2016•2 citations

Steady-state absorption–dispersion properties and four-wave mixing process in a quantum dot nanostructure

Xiangying Hao, Jing Wu, Ying Wang

With the presence of the signal pulse, a quantum dot (QD) four-level structure interacting with four fields forms a double-cascade configuration. The linear optical properties for amplification, absorption, and dispersion of two weak near-infrared (NIR) lights in this scheme are investigated. It shows that the amplification, transparency, normal and anomalous dispersion of the probe and signal fields, i.e., the two NIR waves, can be achieved by adjusting the relative phase of the applied lasers, the probe detuning, and the two pump Rabi energies appropriately, while when the signal pulse is removed, the nonlinear optical phenomenon four-wave mixing (FWM) originating from quantum interference is demonstrated. A highly efficient FWM process with a NIR mixing field generated can be realized in this system. Such investigation in a semiconductor QD system with flexible design and widely adjustable parameters may provide new possibilities for realizing the efficient generation and gain of NIR waves and manipulating light propagation between subluminal and superluminal in the solid-state materials.

Journal of the Optical Society of America B•Feb 22, 2012•39 citations
In this paper, we have realized amplification without inversion (AWI) in quantum dot (QD). A Y-type four-level system of InxGa1-xN quantum dot has been obtained and investigated for AWI. It has been shown that, with proper setting of control fields' amplitude, we can obtain reasonable gain. With proper setting of phase difference of control fields and probe field, we can obtain considerable gain in resonant wavelength. We have designed this system by solving the Schrödinger–Poisson equations for InxGa1-xN quantum dot in GaN substrate, self-consistently.
This study aims to designing quantum dot semiconductor optical amplifier (QD-SOA) by amplification without inversion technique in InxGa1-xN/GaN semiconductor quantum dot (nanostructure). To do this, eigen energies and their corresponding wave functions of a Y-type four-level atomic system were obtained by solving of Schrodinger- Poisson equations self-consistently (considering intersublevel transitions) in InxGa1-xN/GaN quantum dot. The principle of quantum optics to obtain dynamic property of quantum dot density matrix elements was employed and investigated the lasing without inversion (LWI) phenomenon in this quantum dot.
Abstract In this letter, we investigated the behaviors of the absorptive–dispersive properties of weak probe light in a four-level InGaN/GaN quantum dot nanostructure. In order to achieve the wave functions and their corresponding energy levels of the mentioned quantum dot nanostructure, Schrödinger and Poisson equations must be solved self consistently for carriers (here electrons) in quantum dots. The enhanced refractive index with amplification can be obtained via adjusting the corresponding controllable parameters such as intensity, detuning and relative phase of the applied fields. Our proposed scheme provides a realistic model for controlling the index of refraction in a quantum dot nanostructure.
A four-level system driven by two coherent fields is considered. It is shown that in the presence of an incoherent pump, the probe gain at a short wavelength can be achieved due to the quantum interference. Our density matrix calculation provides the conditions for probe amplification from different origins, including gain without population inversion on any state basis, gain with population inversion on the dressed-state basis and gain with population inversion on the bare-state basis. Also, by controlling the Rabi frequency of the coupling field a total change from non-inversion to inversion can be achieved which does not depend on the intensity of the incoherent pump.
The dispersion behaviors of weak probe light in an InGaN/GaN quantum dot (QD) nanostructure driven by a coherent coupling field is investigated. InGaN/GaN QD nanostructure is designed numerically by solving the Schrödinger–Poisson coupled equations. By specific values of QD radius, an appropriate four-level QD nanostructure which is suitable for interaction by a weak probe light and a coherent coupling field is designed. It is shown that switching from normal to anomalous dispersion can be achieved by the intensity of coupling field. Therefore, fast light propagation in this model can be obtained by reduced absorption.
With the presence of the signal pulse, a quantum dot (QD) four-level structure interacting with four fields forms a double-cascade configuration. The linear optical properties for amplification, absorption, and dispersion of two weak near-infrared (NIR) lights in this scheme are investigated. It shows that the amplification, transparency, normal and anomalous dispersion of the probe and signal fields, i.e., the two NIR waves, can be achieved by adjusting the relative phase of the applied lasers, the probe detuning, and the two pump Rabi energies appropriately, while when the signal pulse is removed, the nonlinear optical phenomenon four-wave mixing (FWM) originating from quantum interference is demonstrated. A highly efficient FWM process with a NIR mixing field generated can be realized in this system. Such investigation in a semiconductor QD system with flexible design and widely adjustable parameters may provide new possibilities for realizing the efficient generation and gain of NIR waves and manipulating light propagation between subluminal and superluminal in the solid-state materials.