Sete, Eyob Alebachew.
Quantum Coherence Effects in Novel Quantum Optical Systems.
Degree: PhD, Physics, 2012, Texas A&M University
Optical response of an active medium can substantially be modified when coherent superpositions of states are excited, that is, when systems display quantum coherence and interference. This has led to fascinating applications in atomic and molecular systems. Examples include coherent population trapping, lasing without inversion, electromagnetically induced transparency, cooperative spontaneous emission, and quantum entanglement.
We study quantum coherence effects in several quantum optical systems and find interesting applications. We show that quantum coherence can lead to transient Raman lasing and lasing without inversion in short wavelength spectral regions – extreme ultraviolet and x-ray – without the requirement of incoherent pumping. For example, we demonstrate transient Raman lasing at 58.4 nm in Helium atom and transient lasing without inversion at 6.1 nm in Helium-like Boron (triply-ionized Boron). We also investigate dynamical properties of a collective superradiant state prepared by absorption of a single photon when the size of the sample is larger than the radiation wavelength. We show that for large number of atoms such a state, to a good approximation, decays exponentially with a rate proportional to the number of atoms. We also find that the collective frequency shift resulting from repeated emission and reabsorption of short-lived virtual photons is proportional to the number of species in the sample. Furthermore, we examine how a position-dependent excitation phase affects the evolution of entanglement between two dipole-coupled qubits. It turns out that the coherence induced by position-dependent excitation phase slows down the otherwise fast decay of the two-qubit entanglement. We also show that it is possible to entangle two spatially separated and uncoupled qubits via interaction with correlated photons in a cavity quantum electrodynamics setup. Finally, we analyze how quantum coherence can be used to generate continuous-variable entanglement in quantum-beat lasers in steady state and propose possible implementation in quantum lithography.
Advisors/Committee Members: Scully, Marlan O. (advisor), Zubairy, Muhammad S. (committee member), Kocharovskaya, Olga (committee member), Chen, Goong (committee member).
Subjects/Keywords: Quantum coherence effects; extreme ultraviolet and x-ray lasers; transient lasing without inversion; transient Raman lasing; superradiance; Collective Lamb (frequency) shift; dipole-coupled qubit entanglement; light-to-matter entanglement transfer; quantum beat laser; continuous-variable entanglement; quantum lithography
RAMAN LASING IN XUV AND LASING WITHOUT INVERSION IN X-RAY SPECTRAL REGIONS… …1. Maxwell-Schr¨
odinger equation . . . . . . .
C. Transient Raman lasing in Helium… …Raman lasing and transient lasing without inversion in the short wavelength regimes,
extreme… …as a gain media. We demonstrate transient Raman lasing in Helium
atoms at 58.4 nm and… …TO DEMONSTRATE TRANSIENT RAMAN LASING IN
XUV AND LASING WITHOUT INVERSION IN X-RAY SPECTRAL…
to Zotero / EndNote / Reference
APA (6th Edition):
Sete, E. A. (2012). Quantum Coherence Effects in Novel Quantum Optical Systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11400
Chicago Manual of Style (16th Edition):
Sete, Eyob Alebachew. “Quantum Coherence Effects in Novel Quantum Optical Systems.” 2012. Doctoral Dissertation, Texas A&M University. Accessed October 29, 2020.
MLA Handbook (7th Edition):
Sete, Eyob Alebachew. “Quantum Coherence Effects in Novel Quantum Optical Systems.” 2012. Web. 29 Oct 2020.
Sete EA. Quantum Coherence Effects in Novel Quantum Optical Systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2020 Oct 29].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11400.
Council of Science Editors:
Sete EA. Quantum Coherence Effects in Novel Quantum Optical Systems. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11400