Light-Matter Coupling Regimes of the Quantum Rabi Model — Spectrum, Eigenstates, and Entanglement
(2024) FYSK04 20241Department of Physics
Mathematical Physics
- Abstract
- In this thesis, the eigenenergies and eigenstates of the quantum Rabi model, a foundational model of light-matter interaction, are investigated. The focus lies on three different regimes characterized by the coupling strength: the weak-strong, ultrastrong, and deep-strong regime. To study the quantum Rabi model in these regimes, approximations including the rotating-wave approximation, the Scrieffer-Wolff transformation, and perturbation theory were used. The analysis extends to investigating the probability to observe a certain finite number of photons in the ground state and the entanglement between the light-matter states. Through these findings, a deeper and more intuitive understanding of the physical phenomena described by the... (More)
- In this thesis, the eigenenergies and eigenstates of the quantum Rabi model, a foundational model of light-matter interaction, are investigated. The focus lies on three different regimes characterized by the coupling strength: the weak-strong, ultrastrong, and deep-strong regime. To study the quantum Rabi model in these regimes, approximations including the rotating-wave approximation, the Scrieffer-Wolff transformation, and perturbation theory were used. The analysis extends to investigating the probability to observe a certain finite number of photons in the ground state and the entanglement between the light-matter states. Through these findings, a deeper and more intuitive understanding of the physical phenomena described by the quantum Rabi Model can be reached. (Less)
- Popular Abstract
- Have you ever wondered how light interacts with matter? The study of quantum mechanics has given us a great understanding of this topic in the last hundred years. By researching the way light interacts with matter, we have been able to create technologies that have had a significant impact on humanity, such as x-rays machines. However, there is still much to be discovered about this fascinating phenomenon. In this text, we will discuss what light-matter interactions are, the concept of coupling, and what it means to change the coupling strength.
Light-matter interactions are very important in our day-to-day lives as they are responsible for how we see the world around us. They are also responsible for why the sky is blue, and why you... (More) - Have you ever wondered how light interacts with matter? The study of quantum mechanics has given us a great understanding of this topic in the last hundred years. By researching the way light interacts with matter, we have been able to create technologies that have had a significant impact on humanity, such as x-rays machines. However, there is still much to be discovered about this fascinating phenomenon. In this text, we will discuss what light-matter interactions are, the concept of coupling, and what it means to change the coupling strength.
Light-matter interactions are very important in our day-to-day lives as they are responsible for how we see the world around us. They are also responsible for why the sky is blue, and why you feel warmer under the light of the sun. Light-matter interaction refers to the process of light particles interacting with the electrons present in the atoms of materials. Unlike the type of interactions we observe in our usual lives, such as balls colliding, light-matter interactions are a pure quantum mechanical phenomenon. This comes as a result of the discretization of energy, i.e. energy levels, in quantum mechanics. This can be understood by imagining an empty jar that we fill with marbles. Each marble in this scenario represents one unit, a quanta, of energy. Removing or adding a marble to the jar is equivalent to removing or adding energy from/to our particle. In the mid-20th century, it was discovered that light particles, photons, corresponded to these quantas of energy. Typically, light-matter interactions involve the exchange of energy between photons and electrons through two processes: absorption and emission. Absorption occurs when an electron transitions to a higher energy level (adding a marble to the jar) by absorbing a photon, while emission involves the electron returning to a lower energy level (removing a marble from the jar) and releasing its energy in the form of a photon. These processes lead to light-matter coupling.
Coupling, in physics, refers to the interaction between objects, and the strength of the coupling determines the force with which these objects affect each other. This thesis investigates how variations in the coupling strength impact the interaction between photons and a single electron with two energy levels. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9160752
- author
- Yehya, MHD Mahmoud LU
- supervisor
- organization
- course
- FYSK04 20241
- year
- 2024
- type
- M2 - Bachelor Degree
- subject
- keywords
- Light-Matter Interactions, Light-Matter Coupling, Quantum Rabi Model, Jaynes-Cummings Hamiltonian, Bloch-Siegert Hamiltonian, Deep-Strong Coupling Regime, Entanglement
- language
- English
- id
- 9160752
- date added to LUP
- 2024-06-10 10:41:05
- date last changed
- 2024-06-10 10:41:05
@misc{9160752,
abstract = {{In this thesis, the eigenenergies and eigenstates of the quantum Rabi model, a foundational model of light-matter interaction, are investigated. The focus lies on three different regimes characterized by the coupling strength: the weak-strong, ultrastrong, and deep-strong regime. To study the quantum Rabi model in these regimes, approximations including the rotating-wave approximation, the Scrieffer-Wolff transformation, and perturbation theory were used. The analysis extends to investigating the probability to observe a certain finite number of photons in the ground state and the entanglement between the light-matter states. Through these findings, a deeper and more intuitive understanding of the physical phenomena described by the quantum Rabi Model can be reached.}},
author = {{Yehya, MHD Mahmoud}},
language = {{eng}},
note = {{Student Paper}},
title = {{Light-Matter Coupling Regimes of the Quantum Rabi Model — Spectrum, Eigenstates, and Entanglement}},
year = {{2024}},
}