Quantum state control of two interacting rydberg atoms

Abstract

The field of ultracold Rydberg atoms has made enormous progress in recent yearsand emerges at the forefront to probe quantum properties of matter Individuallycontrolled Rydberg atoms prove to be a versatile platform to test phenomena significant to condensed matter physics quantum optics atomic and molecular physics Systems of many body interacting Rydberg atoms have an enormous potential tosolve long standing problems in physics On the other hand the interest in two body Rydberg systems is motivated by applications of local quantum control anddeterministic local state preparation in a larger array Our work pertains to manipulating the state dynamics of the two atom system which is achieved by tuningthe atom light couplings and detunings both in weakly and strongly interactingsystems First we investigate the effect of an offset in Rabi coupling between two Rydbergatoms both in coherent and dissipative systems The interplay of Rabi frequency offset and tunable interactions reveals fascinating features In the strongly interactingregime we find a novel phenomenon of Rydberg biased freezing where amplificationof the Rabi frequency of one atom suppresses the dynamics in the second atom Inthe weak interaction regime we discuss the double excitation dynamics as a function of interaction for very small offsets in the Rabi frequencies We further proposea dynamic control over quantum correlations upon dynamic variation of the Rabifrequency of the second atom In the second part of the thesis we use time dependent atom laser detuning tomanipulate collective quantum states We first consider a linear variation of thedetuning We observe that for different values of Rydberg Rydberg interaction thesystem can emulate different three level Landau Zener models such as bow tie andtriangular Landau Zener models Our central result is that Landau Zener excitationdynamics exhibit nontrivial dependen newline newline