Super dense coding out of thermal equilibrium

Abstract

We have examined the potentiality of superdense coding for a quantum system placed out of thermal equilibrium. To this aim, the dynamics of two two-level quantum systems are analyzed and explicit expressions for transition rates are evaluated. The dependence of superdense coding capacity on initial states is observed and examined for different ratios of anti-symmetric to symmetric transition rates. The effect of sub-radiant and super-radiant terms is interpreted. The validity of dense coding is also analyzed for different probability amplitudes and it is perceived that maximally entangled states show the highest degree of coding capacity. Moreover, the optimal time of coding capacity is greatest for initially entangled state. This strategy can be relevant to analyze further applications out of thermal equilibrium.