The Electromagnetically Induced Transparency In Dressed Superconducting Quantum Bits

With the development of quantum information, quantum computation shows the greatpotential which encourages the scientists. Scientists and engineers conceived a kind of brand-new information processing mechanism, whose performance will be exponential growth andbe much better than the current computer. Because the superconducting quantum bits(SQUBIT) has the characteristics of strong coupling, it is easy to use inductor, capacitor andtransmission line to structure multi-level system with complex topology structure; And due tothe SQUBIT has macroscopic size, it is easy to use micro-nano machining platform to realizeintegration. In recent years, SQUBIT based on Josephson junction shows macroscopicquantum effect which has attracted widespread attentions, and it is regarded as one of thepromising way to realize quantum computation.Different from the past, we study a SQUBIT based on Josephson junction, whichinteracts with a dress field forming a dressed-SQUBIT. We consider a dressed SQUBITinteracting with a single control field which forms a-type three level system, and study theelectromagnetic induced transparency (EIT) phenomenon of this system which under strongcoupling of the control field, we also study the influence of the detuning of dress filed andcontrol filed. On this basis, we consider a dressed SQUBIT interacting with two control fieldforms an inverted Y-type four level system. We also analysis the influence of the dress filedand control filed, and study the transient evolution when turning on the control filed.We use semi-classical method to research the dressed SQUBIT, and find the switchingphenomenon: By varying the detuning of the dress filed, the system can transformationbetween electromagnetic induction absorption (EIA) and EIT. For a Y-type of four-levelsystem, when shut down one of the control field, the four-level system degenerate into aclassic-type three level system or-type three level system. At the same time, thecoupling strength of the control field influence of EIT phenomenon, and the detuning of thecontrol field has obvious influence on EIT phenomenon, too. Finally, we study the transientevolution behaviors of the inverted Y-type four level system, we find that the system canstabilize at a few hundred nanoseconds and shows absorption or transparent to the probe field.This can be applicable to designs of some new quantum storage devices.In this paper, the main content and structure are as follows: the first chapter mainlyintroduces the research background and personal work; The second chapter mainly introduces the basic concepts and the research methods used in this paper; The third chapter mainlyintroduces a-type three level system based on dressed SQUBIT; The fourth chaptermainly introduces an inverted Y-type four level system based on SQUBIT; The last chapteris a summary.