Two measures elaborated for entangled states: Quantum entropy and fidelity using Schmidt coefficients of the reduced density matrix of full TRI


  • Rasim Dermez Afyon Kocatepe University
  • Y. Tunçer Usak University



Qudit states, fidelity, the total density operator, quantum correlations.


In the present study, we determined quantum entanglement in a full trapped ion (TRI)-coherent system and its dependence on the LambDicke parameter (LDP). We investigated the entanglement in view of two elaborated measurements of the family: entropy and fidelity. We selected three values of the deep LDP to demonstrate the benefits of these two critical measures. The findings obtained in this study showed that the maximum value of fidelity for entangled states is quantified approximately to be 0.35, and the long lifetime is also observed with entropy measurement. The findings suggest that three coupling parameters play a significant role in developing quantum entanglement.


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How to Cite

R. Dermez and Y. Tunçer, “Two measures elaborated for entangled states: Quantum entropy and fidelity using Schmidt coefficients of the reduced density matrix of full TRI”, Rev. Mex. Fís., vol. 68, no. 5 Sep-Oct, pp. 050703 1–, Aug. 2022.



07 Gravitation, Mathematical Physics and Field Theory