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Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Adopting the continuous frequency mode approach and the resolvent method, we study the interaction between atoms and photons in leaky optical cavities. In particular, we highlight the physical significance of quantum states of photons in such processes. Single-photon processes and two-photon processes are intensively investigated. With single-photon scattering, various schemes for generating entangled pairs and constructing quantum gates are developed using two-level atoms or Λ-type atoms. The fidelities of these schemes tend to unity for injected photons with specific spectra. We examine the efficiency of the feedback scheme proposed by Hong and Lee [Phys. Rev. Lett. 89 , 237901 (2002)] to generate maximally entangled states of two atoms in an optical cavity from first principles. We find that the efficiency of the scheme deteriorates gradually and hence other competing processes have to be considered properly. Besides, nonlinearity and entanglement of two-photon states in two-sided and one-sided cavities are analyzed in terms of detection probabilities and frequency-correlation of the left- and right-output photons. We discover that two-photon processes in a one-sided cavity can be exploited to generate two-photon maximally entangled states, from which nonlocal shaping effect in the spectra of the two photons can be demonstrated. Lastly, based on the Fredholm method, an iterative analytical method yielding the Schmidt modes and eigenvalues of an entangled state is proposed and discussed. / Fung, Ho Tak = 光子與原子在漏空腔中的糾纏及其在量子計算中的應用 / 馮浩德. / "May 2008." / Adviser: P. T. Leung. / Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1736. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 155-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307. / Fung, Ho Tak = Guang zi yu yuan zi zai lou kong qiang zhong de jiu chan ji qi zai liang zi ji suan zhong de ying yong / Feng Haode.

Tsoi, Tze Shun = 光子和原子在一維波導中的相互作用 / 蔡子淳. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 94-97). / Abstract also in Chinese. / Tsoi, Tze Shun = Guang zi he yuan zi zai yi wei bo dao zhong de xiang hu zuo yong / Cai Zichun. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Basic description of QED in a one-dimensional waveguide --- p.4 / Chapter 2.1 --- EM fields in a waveguide: from classical to quantum --- p.4 / Chapter 2.1.1 --- Classical EM fields in a conducting waveguide --- p.5 / Chapter 2.1.2 --- Quantization of the electromagnetic fields --- p.8 / Chapter 2.2 --- "Atom, dipole interactions and interaction models" --- p.11 / Chapter 2.2.1 --- Atom and dipole interactions --- p.12 / Chapter 2.2.2 --- Two-level atom --- p.12 / Chapter 2.2.3 --- A-atom --- p.14 / Chapter 2.3 --- Comparison: waveguide vs free space --- p.15 / Chapter 2.3.1 --- Electric field intensity of a photon packet --- p.15 / Chapter 2.3.2 --- Spontaneous decay rate --- p.16 / Chapter 3 --- Single-excitation solution for two-level atoms --- p.20 / Chapter 3.1 --- Case of a single atom --- p.20 / Chapter 3.2 --- Case of a chain of N identical atoms --- p.26 / Chapter 3.2.1 --- The Hamiltonian and eigenvectors --- p.27 / Chapter 3.2.2 --- Transmission spectrum of a single photon --- p.31 / Chapter 3.2.3 --- Dynamics of spontaneous emission --- p.34 / Chapter 3.3 --- Dissipative loss to non-waveguide modes --- p.39 / Chapter 3.4 --- Interactions with non-identical atoms --- p.41 / Chapter 3.4.1 --- Vacuum Rabi oscillations using atomic mirrors --- p.42 / Chapter 3.4.2 --- Atoms with non-identical resonant energies --- p.46 / Chapter 4 --- Two-photon transport with a two-level atom --- p.50 / Chapter 4.1 --- The energy eigenstate solution --- p.51 / Chapter 4.1.1 --- Single-photon case --- p.51 / Chapter 4.1.2 --- Two-photon case --- p.53 / Chapter 4.2 --- Laplace transformation method --- p.57 / Chapter 4.2.1 --- Single-photon case --- p.58 / Chapter 4.2.2 --- Two-photon case --- p.61 / Chapter 4.2.3 --- Lorentzian-packet states --- p.64 / Chapter 4.2.4 --- Photon-photon correlations --- p.65 / Chapter 5 --- Interactions with A-atoms --- p.70 / Chapter 5.1 --- Hamiltonian and eigenvectors --- p.71 / Chapter 5.1.1 --- N = 1 case --- p.71 / Chapter 5.1.2 --- N > 1 case --- p.75 / Chapter 5.2 --- Final state properties --- p.80 / Chapter 5.2.1 --- Polarization dependent transmission and reflection --- p.80 / Chapter 5.2.2 --- Collective atomic states --- p.82 / Chapter 5.2.3 --- Scattering with a photon wave packet --- p.83 / Chapter 5.3 --- Decoherence: effects of the coupling with the non-waveguide modes --- p.85 / Chapter 5.4 --- Application: an “NM´ح polarizer made of a few atoms --- p.86 / Chapter 6 --- Conclusion --- p.91 / Bibliography --- p.94 / Chapter A --- Derivation of the one-dimensional spontaneous rate r1d --- p.98 / Chapter B --- Description of a photon packet --- p.101 / Chapter C --- Derivation of the two-photon packet solution --- p.105 / Chapter D --- “Completeness´ح of the two-photon Lorentzian-packet states --- p.108

Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. The reduction of radium by photonuclear transmutation by bombarding Ra-226 with high-energy photons from a medical linac has been investigated. The irradiated needles would then be processed to remove the Ac-225, which can then be used for .Targeted Alpha Therapy. (TAT) of cancer. This project has the potential to slowly reduce obsolete radioactive material, and displace future expensive importation of Ac-225 from Russia, Germany (Institute for Transuranium Elements - ITU) and the US in the years ahead. This thesis progresses through a number of stages and begins by providing a background to the usefulness of Ac-225 as an alpha emitter, some of the equipment used in the experimental work such as linear accelerators and detectors, as well as the initialisation of a process whereby a reliable source of high-grade radium is secured, suitable equipment obtained, followed by a series of experiments leading to the production of the desired product, actinium and bismuth. The second stage of this study involved the formulation of a theoretical model in which the bremsstrahlung photon spectrum at 18 MV linac electron energy is convoluted with the corresponding photonuclear cross sections of Ra- 226. This enabled the total integrated yield of Ra-225 and its daughter product Ac-225 to be obtained. The third stage of this study ties the theoretical and experimental work together by presenting the results of a number of experiments performed on radium sources. These experiments were performed over a period of about three years using a variety of detectors in a hospital setting. These experiments, as presented in this thesis, demonstrate that Ac-225 can be produced in small quantities by a medical linac or in commercial quantities by the use of a high-powered linac or cyclotron, thereby, ensuring a reliable supply of Ra-225 for TAT and also reducing the radium waste product. / Doctor of Philosophy

Thesis (Ph.D.)--University of California, Berkeley, 1961. / "Physics, UC-34" -t.p. "TID-4500 (16th Ed.)" -t.p. Includes bibliographical references (p. 43-44).

Thesis (Ph.D.)--University of California, Berkeley, 1961. / "Physics UC-34" -t.p. "TID-4500 (16th Ed.)" -t.p. Includes bibliographical references (p. 57-58).

Thesis (Ph. D.)--Physics, Georgia Institute of Technology, 2007. / Kennedy, T. A. Brian, Committee Chair ; Kuzmich, Alex, Committee Member ; Chapman, Michael S., Committee Member ; Raman, Chandra, Committee Member ; Morley, Thomas D., Committee Member.

A measurement of the differential cross section has been performed for the photodisintegration of ⁴He into a proton plus a triton. This reaction is highly sensitive to the electromagnetic currents in the nucleus which arise from the exchange of mesons between nucleons. The study of light nuclei such as ⁴He, whose nucleonic structure is the simplest, holds the promise of perfecting a microscopic theory of nuclear dynamics, in which nuclear structure and reactions are understood in terms of fundamental particle interactions. The measurement was performed with a tagged-photon beam, using a large solid-angle charged particle detector developed for this and other similar experiments. The measurement was performed within the photon energy range between 63 and 71 MeV, and divided into four energy bins of 2 MeV each. The measurement of the differential cross section was confined to the angular range 36°-141° in the center-of-mass reference frame. The total cross section was determined to within a total uncertainty of 5%. The angular distribution was fitted to an expansion of Legendre polynomials in cos <i>θ</i> including terms of order 0-3. This measurement is in agreement with a previous measurement, and improves on the precision of the total cross section from the previous measurement by a factor of 6. A comparison is made with several theoretical calculations, and a qualitative agreement is found. These data suggest refinements to these calculations, in order to account for the quantitative differences. / Ph. D.

本論文包含兩個主題。第一部分研究無旋轉波近似下幾種原子與光的相互作用。第二部分研究駐波場耦合的電磁自感透明系統的反射和透射。它們的簡介如下。 / 第一部分。旋轉波近似即忽略掉原子與光相互作用哈密頓量中的反旋轉波項。它的有效性來自於能量守恆定律。但是在時間尺度非常小的情況下，根據海森堡不確定性原理，能量的不確定性可以很大，所以旋轉波近似不能應用于短時間行為的研究，比如量子芝諾和反芝諾效應，蘭姆位移，非共振極化以及超輻射和亞輻射中的能移。為超越旋轉波近似，我們對哈密頓量採用了么正變換。在變換之後的基矢之間，只有由帶修正係數的旋轉波項造成的躍遷。 / 我們從原子和真空的相互作用開始。對於氫原子來說，自由真空中沒有量子反芝諾效應，但是如果對真空態密度用腔或特異性材料做一些調製，量子反芝諾效應就會出現，蘭姆位移也會改變。我們接著研究原子和非真空光場的相互作用。我們計算了滿足光學定理的兩能級原子極化率。然後我們把么正變換用到了兩個全同原子和真空的相互作用，並計算了超輻射和亞輻射的輻射譜以及量子芝諾和反芝諾效應。 / 第二部分。在電磁自感透明系統裏，如果耦合光場為駐波，介質的極化率就會受到週期性調製而形成一維光子晶體。和傳統的傳輸矩陣不同的是，我們採用了麥克斯韋-劉維爾耦合波方程來處理這個系統並得到了光子晶體能帶的一個新的評判標準。起關鍵作用的物理量為非線性耦合係數除以波矢錯差和線性極化率的和，也就是非線性因素除以線性因素。 / 首先，我們研究了光子能帶的位置和寬度與實驗參數的量化關係。然後我們研究了溫度升高时光子晶體的融化以及向多普勒無關的多波混頻的轉化。如果在兩束對向傳播的耦合場之間引入失諧，駐波場的包絡會形成一個“飛行“的光子晶體。因為多普勒效應，順著飛行方向或者逆著飛行方向的探測光在一維光子晶體的坐標系裏具有不同的頻率。在靜止坐標系看，透射譜會在頻率上錯開並形成光學二極體。 / This thesis includes two topics. Part 1 is on the various atom-photon interactions without rotating-wave approximation (RWA). Part 2 is on the reflection and transmission in a standing wave coupled electromagnetically induced transparency (EIT) system. / Part 1. In the RWA, the counter-rotating terms in the atom-photon interaction Hamiltonian are neglected. Its validity is the result of energy conservation. However, if the time scale is sufficiently small, the uncertainly in the energy can become large, according to the Heisenberg uncertainty principle. Thus the RWA can not be applied in the study of the short time behavior, such as the quantum Zeno effect (QZE) and anti-Zeno effect (QAZE), the Lamb shift, the non-resonant polarizability and shifts in the superradiance and subradiance. To go beyond RWA, we apply a unitary transformation on the Hamiltonian. In the transformed basis, there are only secular transitions due to rotating terms with modified coupling constants. / We start from the interactions between atom and vacuum. For the hydrogen atom, there is no QAZE in free vacuum. However, with the modification in the density of states of the vacuum by a cavity or a meta-material, the QAZE appears and the Lamb shift changes. We then turn to the atom in light field, where the polarizability of a two-level atom is calculated and the results satisfy the optical theorem. The unitary transformation is then applied to two identical atoms interacting with vacuum. Their various emission spectra of the superradiance and subradiance and the QZE and QAZE are studied. / Part 2. In an EIT system, if the coupling field is a standing wave, the susceptibility of the medium is periodically modified to form a one-dimensional photonic crystal (1DPC). In contrast to the conventional treatment with transfer matrix, we use Maxwell-Liouville coupled-wave equations and propose new criteria for the bandgap of the photonic crystal (PC). The relevant quantity is the ratio between the nonlinear coupling coefficient and the wave vector mismatch plus the linear susceptibility, which is the nonlinear effect over the linear effect. / First, we study the quantitative relation between the position and width of the photonic bandgap and the experimental parameters. We then show that, as the temperature rises, the 1DPC melts down and enters the Doppler-free wave-mixing regime. By introducing detuning between the two counter-propagating fields in the standing wave, we make the envelope of the standing wave move and form a ‘flying’ 1DPC. Owing to the Doppler Effect, the probe fields propagating along with or counter to the moving direction have different frequencies in the 1DPC frame. In the rest frame, the transmission spectra in two directions are thus shifted with respect to each other and we obtain an optical diode. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wang, Dawei = 無旋轉波近似下原子-光子相互作用和駐波耦合的電磁自感透明系統 / 王大偉. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 128-135). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Wang, Dawei = Wu xuan zhuan bo jin si xia yuan zi-guang zi xiang hu zuo yong he zhu bo ou he de dian ci zi gan tou ming xi tong / Wang Dawei. / Abstract --- p.iv / Acknowledgements --- p.vii / Table of Contents --- p.xi / List of Figures --- p.xiii / Chapter Part 1 --- Atom-photon interactions without rotating-wave approximation --- p.1 / Chapter Chapter 1 --- Introduction on atom-photon interactions --- p.2 / Chapter 1.1 --- Spontaneous emission --- p.2 / Chapter 1.2 --- Quantum Zeno and anti-Zeno effect --- p.8 / Chapter 1.3 --- Rotating-wave approximation --- p.10 / Chapter 1.4 --- Go beyond the rotating-wave approximation --- p.12 / Chapter 1.5 --- Non-dynamic Lamb shift --- p.15 / Chapter 1.6 --- Summary --- p.17 / Chapter Chapter 2 --- QZE, QAZE and Lamb shift in vacuum --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.2 --- QZE in the free vacuum --- p.19 / Chapter 2.3 --- QAZE in modified vacuum --- p.21 / Chapter 2.4 --- Time Evolution of the Lamb Shift --- p.25 / Chapter 2.5 --- The Lamb shift in modified vacuum --- p.30 / Chapter 2.6 --- Summary --- p.35 / Chapter Chapter 3 --- Atom in light: polarizability and scattering --- p.37 / Chapter 3.1 --- Introduction --- p.37 / Chapter 3.2 --- The polarizability of a two-level atom without RWA --- p.39 / Chapter 3.3 --- The optical theorem --- p.43 / Chapter 3.4 --- The effects of the counter rotating terms --- p.46 / Chapter 3.5 --- The frequency shift --- p.48 / Chapter 3.6 --- Summary --- p.50 / Chapter Chapter 4 --- Spontaneous emission of two identicalatoms --- p.51 / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.2 --- Unitary transform of the Hamiltonian --- p.52 / Chapter 4.3 --- Dynamicevolution --- p.57 / Chapter 4.4 --- Decay rates, Lamb shift and emission spectrum in the longtime limit --- p.59 / Chapter a) --- The decayrates --- p.59 / Chapter b) --- The Lamb shift --- p.60 / Chapter c) --- The emission spectra --- p.62 / Chapter 4.5 --- Short time evolution --- p.68 / Chapter 4.6 --- Summary --- p.70 / Chapter Appendix --- the shifts and decay rates of the symmetric and anti-symmetric states --- p.71 / Chapter Part 2 --- Standing wave coupled electromagnetically induced transparency system --- p.74 / Chapter Chapter 5 --- Introduction on electromagnetically induced transparency --- p.75 / Chapter 5.1 --- The electromagnetically induced transparency --- p.75 / Chapter 5.2 --- The susceptibilities of SWEIT --- p.81 / Chapter 5.3 --- Summary --- p.86 / Chapter Appendix --- the recursion relation and the proof of Eq.(212) --- p.86 / Chapter Chapter 6 --- From photonic crystal to Doppler-free wave-mixing --- p.90 / Chapter 6.1 --- Introduction --- p.90 / Chapter 6.2 --- The Maxwell-Liouville equations --- p.91 / Chapter 6.3 --- The photonic bandgaps --- p.93 / Chapter 6.4 --- The meltdown of the photonic crystal and the pulse matching --- p.99 / Chapter 6.5 --- Summary --- p.106 / Chapter Appendix A --- the Maxwell-Liouville equation --- p.106 / Chapter Appendix B --- a new criterion of photonic band-gaps --- p.109 / Chapter Chapter 7 --- The optical-diode by a flying photonic crystal --- p.112 / Chapter 7.1 --- Introduction --- p.112 / Chapter 7.2 --- Coupled-wave equations of the ‘flying’ photonic crystal --- p.113 / Chapter 7.3 --- The spectra of the optical diode --- p.118 / Chapter 7.4 --- The influence of the experimental parameters --- p.120 / Chapter 7.5 --- Summary --- p.126 / CURRICULUM VITAE --- p.136