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| Author(s): |
José Gabriel Aguirre Gómez
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Física (IF/SBI) |
| Defense date: | 2004-03-26 |
| Examining board members: |
Paulo Alberto Nussenzveig;
Joao Carlos Alves Barata;
Kaled Dechoum;
Maria Aparecida Gonçalves Martinez;
Sebastiao Jose Nascimento de Padua
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| Advisor: | Paulo Alberto Nussenzveig |
| Abstract | |
In this work we present experimental and theoretical results of intensity and phase noise, and of the correspondent correlations, between pump and probe fields in electromagnetically induced transparency. Experimentally, in this condition, we measure intensity excess-noise in both beams as well as intensity correlations and anti-correlations, clearly showing that both are dependent on the fields intensities and on the analysis frequency. We also observed structures in the noise spectra of the fields in the induced transparency and that, in a single spectrum, there are zones with correlation and anti-correlation of intensity, interchanged. These structures are dependent, again, on the fields intensities and on the analysis frequency. We also measured excess phase noise in our beams and, for the first time, we measured a phase noise correlation between the beams in the condition of induced transparency. Theoretically, we further developed an analysis with a model in which the atoms and the fields are treated quantum-mechanically. Owing to limitations detected in the application of this model to our experimental situation, we developed a new semi-classical model, in which the fields present phase diffusion. The new predictions obtained show a good qualitative agreement with the experimental result features. The excess noise of intensity of the beams, in the electromagnetically induced transparency, is a result of the resonant transfer of the diode lasers excess phase noise into intensity noise by interaction with the atoms. (AU) | |