Progress towards strong coupling between collisionally blockaded atoms and an optical cavity

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2009.Includes bibliographical references (p. 83-85).In this thesis, I present the motivation and design for an experiment in which to probe the interactions between an atom and a single photon light field. I discuss the relevant technical considerations and many of the physical phenomena that can be tested with this particular experimental system. In particular, I discuss the design, implementation, and control of a high finesse cavity overlapped with a 2pm dipole trap. The use of a relatively long (14mm) cavity grants good optical access, permitting the implementation of a dipole trap centered on the cavity, and small enough to capture only a single atom in the collisional blockade regime.by Alexander Themis Papageorge.S.B

Bichromatic Driving of a Solid State Cavity QED System

The bichromatic driving of a solid state cavity quantum electrodynamics system is used to probe cavity dressed state transitions and observe coherent interaction between the system and the light field. We theoretically demonstrate the higher order cavity-dressed states, supersplitting, and AC stark shift in a solid state system comprised of a quantum dot strongly coupled to a photonic crystal cavity for on- and far off-resonant cases. For the off-resonant case, phonons mediate off-resonant coupling between the quantum dot and the photonic resonator, a phenomenon unique to solid state cavity quantum electrodynamics.Comment: 8 pages 6 figure

Estimation of semiparametric models when the criterion function is not smooth

Includes bibliographical referencesAvailable from British Library Document Supply Centre- DSC:3597. 442(03/450) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Evolutionary Comparison of Ribosomal Operon Antitermination Function▿

Transcription antitermination in the ribosomal operons of Escherichia coli results in the modification of RNA polymerase by specific proteins, altering its basic properties. For such alterations to occur, signal sequences in rrn operons are required as well as individual interacting proteins. In this study we tested putative rrn transcription antitermination-inducing sequences from five different bacteria for their abilities to function in E. coli. We further examined their response to the lack of one known rrn transcription antitermination protein from E. coli, NusB. We monitored antitermination activity by assessing the ability of RNA polymerase to read through a factor-dependent terminator. We found that, in general, the closer the regulatory sequence matched that of E. coli, the more likely there was to be a successful antitermination-proficient modification of the transcription complex. The rrn leader sequences from Pseudomonas aeruginosa, Bacillus subtilis, and Caulobacter crescentus all provided various levels of, but functionally significant antitermination properties to, RNA polymerase, while those of Mycobacterium tuberculosis and Thermotoga maritima did not. Possible RNA folding structures of presumed antitermination sequences and specific critical bases are discussed in light of our results. An unexpected finding was that when using the Caulobacter crescentus rrn leader sequence, there was little effect on terminator readthrough in the absence of NusB. All other hybrid antitermination system activities required this factor. Possible reasons for this finding are discussed