臺灣博碩士論文加值系統

在這篇論文中,我們首先研究金屬奈米線上表面電漿子在線性與非線性的色散關係下與量子點偶合時的傳輸性質。透過解開系統的本徵方程式,我們發現在穿透係數出現的Fano-like譜線跟兩個量子點能階的糾纏是有所關聯的。論文第二個部份,我們探討了一種由原子系綜系統所形成的腔量子電動力學(Cavity QED),把這些原子放在特定的位置時,可以達到強耦合的組態,同時腔中的原子處在激發態的機率會出現類似Rabi振盪的行為。我們進一步使用Leggett-Garg不等式來測試這個系統的量子效應。

In this thesis, we first study the double quantum dots coupled to the surface plasmons with linear and parabolic dispersion relations. Analytical expressions are obtained for the transmission and reflection spectra by solving the corresponding eigenvalue equations. We find that the Fano line shape appears in the transmission spectrum, and there exists correlation between the two-dot entanglement and the Fano resonance. In the second part, a method to enhance the cavity QED coupling by using an ensemble of atoms has been discussed. By placing these atoms in specified locations, one can obtain a strong cavity QED configuration. With an impurity atom in the cavity, the strong coupling may be reached and the excitation dynamics reveals the Rabi-like oscillations. We further examine the quantum coherence of this system by using the Leggett-Garg inequality.

1 Introduction 1
2 Transport properties of nanowire surface plasmons 3
2.1 Model and formulas in different dispersion relations 3
2.2 Transport properties of two quantum dots coupled to surface plasmons 8
2.3 Fano resonance of the scattering spectrum 9
2.4 Entanglement and Fano resonance 11
2.5 Conclusion 18
3 Atomic Cavity QED 19
3.1 The Model 19
3.2 Spin model to the cavity QED configuration 22
3.3 The Leggett-Garg inequality 25
3.4 Conclusion 27
4 Summary and outlooks 28
A Transformation of Hamiltonian from wave-vector-space to real space 31
B Maxwell-Bloch equations 33
Reference 35

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