PN-IV-P8-8.3-ROMD-2023-0013

PROJECT TITLE (ROMANIAN)

Corelatii Cuantice in Sisteme cu Punct Cuantic Dublu Cuplat Neliniar cu un Microrezonator

PROJECT TITLE (ENGLISH)

Quantum Correlations in a Double Quantum Dot System Nonlinearly Coupled with a Microresonator

PROJECT ACRONYM

QuCQD

PROJECT EXECUTIVE SUMMARY (ROMANIAN)

Va fi investigată dinamica cuantică a unui sistem format dintr-un punct cuantic dublu ce interacționează neliniar cu modul unui microrezonator. În mod special va fi avută in vedere situația realistă in care frecvența principală a punctului cuantic dublu este egală cu un multiplu al frecvenței rezonatorului cuantic. În acest context, dinamica cuantică ce descrie sistemul neliniar studiat este complexă și poate conduce la rezultante interesante.

Obiectivele acestui proiect constau în:

- Demonstrarea relației dintre curentul electric ce trece prin punctul cuantic dublu și câmpul electromagnetic din modul rezonatorului cuplat neliniar, și studierea posibilităților de a le controla reciproc;

- Demonstrarea naturii cuantice a corelațiilor fotonilor generați în rezonator și a interconexiunii cu fluctuațiile cuantice ale curentului electric.

Aceste obiective sunt importante in vederea înțelegerii funcționării diferitor dispozitive optice precum amplificatoarele cuantice sau întrerupătoarele cuantice în domeniul de frecvență al microundelor.

 

Project description 

The scope: The aim of this project is to theoretically investigate the quantum dynamics of a compound sample consisting from a double quantum dot system nonlinearly coupled with a leaking single-mode microresonator and predicting potential applications towards engineering optical devices such as quantum amplifiers or optical switchers in the microwave frequency range, respectively. 

Key words: Double Quantum Dot, Microresonator, Quantum Correlations, Electrical Current 

 

PROJECT EXECUTIVE SUMMARY (ENGLISH)

The quantum dynamics of a compound sample consisting of a double quantum dot system which is nonlinearly coupled with a leaking single-mode microresonator will be theoretically investigated. Especially, we shall focus on experimentally achievable resonance condition where resonator multiple frequency equals to the transition frequency of the double quantum dot. As a result, the  quantum dynamics of this complex nonlinear system may exhibit a rich variety of possible effects that have to be identified.

Therefore, the objectives of the present project are to demonstrate:

- The relationship among the electrical current through a double quantum dot and the microwave field inside the resonator that is nonlinearly coupled to it, and to find a way for a mutual influence on each other;

- Quantum correlations of the photon flux generated into the resonator mode and their interconnection to the electrical current fluctuations.

These objectives would be relevant for engineering optical devices such as quantum amplifiers or optical switchers in the microwave frequency range.

 

PROJECT DURATION (MONTHS):  24

NUMBER OF PARTNERS (INCLUDING COORDINATOR): 2

 

Research Team Members

Coordinator

Institutul National de Cercetare-Dezvoltare pentru Fizica si Inginerie Nucleara "Horia Hulubei",       IFIN-HH, Magurele

 

Principal Investigator:  Dr. Aurelian Isar,  Scientific Researcher I

Postdoctoral Member: Dr. Tatiana Mihaescu

PhD Student Member: Alina Stoica

 

Partner 

Moldova State University, Institute of Applied Physics, Chisinau, Moldova

Partner Leader:           Dr. habil. Mihai A. Macovei, Principal Scientific Researcher,                                                                          Head of Theory Group on Quantum Photonics

Postdoctoral Member: Dr. Victor Ceban

PhD Student Member: Elena Cecoi

 

Seminars in Department of Theoretical Physics

Artificial atoms in optomechanics
Speaker: Victor Ceban (Institute of Applied Physics, Chisinau, Moldova) | Date & Time: 05 Sep 2024, 12:00 p.m.

Single- and multi-qubit effects in various quantum environments
Speaker: Mihai Macovei (Institute of Applied Physics, Chisinau, Moldova) | Date & Time: 18 Nov 2024, 12:00 p.m.

Published articles

 

Tatiana Mihaescu, Mihai A. Macovei, Aurelian Isar

Non-Linear Quantum Dynamics in Coupled Double-Quantum-Dot-Cavity Systems

Physics 7(4), 47 (2025) 

https://doi.org/10.3390/physics7040047

 

Tatiana Mihaescu, Aurelian Isar, Mihai A. Macovei

Two-quanta processes in coupled double-quantum-dot cavity systems

European Physical Journal Plus 140, 1194 (2025)  

https://arxiv.org/abs/2501.05967  

https://link.springer.com/article/10.1140/epjp/s13360-025-07150-x

 

MAIN RESULTS OBTAINED 

The relationship between the electric current, passing through the double quantum dot, and the electromagnetic field of a cavity nonlinearly coupled to a double quantum dot (DQD). 
In particular, depending on the Coloumb interaction:

i) It was calculated the average number of photons in the cavity mode and the electric current passing through the DQD. It was established that the latter follows the behavior of the average number of photons in the steady state of the cavity mode and, consequently, a critical behavior occurs, that can lead to the engineering of quantum switches in the microwave frequency range. 

ii) It was established that the concordance between the current and the average number of photons 
is observed only at values of the cavity-DQD coupling parameter higher than the threshold one. 

iii) Respectively, lasing effects also occur in these frequency ranges, while the electric current is 
converted into a photon flux. 

 

COGNITIVE AND SOCIAL-ECONOMIC IMPACT OF THE OBTAINED RESULTS


The project is of a fundamental type, in a modern frontier field and it can be expected that the obtained results, freely disseminated through scientific publications, and presented at various 
conferences or seminars, will continue to attract the attention of the scientific community.  Respectively, they will be of interest to bachelor's or master's students, or doctoral students 
in profile or related specialties.