In this paper, the probabilistic quantum deletion machine constructed from the NB-deletion machine, controlled by the deletion probability p and the error probability q. It is observed that, under specific conditions, controlled errors can enhance the deletion process: when p is minimal and q is maximal, both deletion and retention fidelities reach their optimal values. Compared to the original NB-machine, this probabilistic machine performs better in both deleting and preserving states. Although the output states do not violate Bell’s inequalities, they still achieve teleportation fidelities above the classical limit. The entanglement of machine’s output state appears only when p > 0, and the mixedness increases with p. Altogether, these results indicate that controlled error can enhance certain non-local features of a probabilistic deletion machine.In this paper, the probabilistic quantum deletion machine constructed from the NB-deletion machine, controlled by the deletion probability p and the error probability q. It is observed that, under specific conditions, controlled errors can enhance the deletion process: when p is minimal and q is maximal, both deletion and retention fidelities reach their optimal values. Compared to the original NB-machine, this probabilistic machine performs better in both deleting and preserving states. Although the output states do not violate Bell’s inequalities, they still achieve teleportation fidelities above the classical limit. The entanglement of machine’s output state appears only when p > 0, and the mixedness increases with p. Altogether, these results indicate that controlled error can enhance certain non-local features of a probabilistic deletion machine.

International Conference on Next-Gen Quantum and Advanced Computing: Algorithms, Security, and Beyond (NQComp)Mar 5, 20260 citations

Strategies for state-dependent quantum deleting

Wei Song, Ming Yang, Zhuo‐Liang Cao

Physics Letters AJun 1, 20041 citation

Quantum deletion: Beyond the no-deletion principle

Satyabrata Adhikari

Suppose we are given two identical copies of an unknown quantum state and we wish to delete one copy from among the given two copies. The quantum no-deletion principle restricts us from perfectly deleting a copy but it does not prohibit us from deleting a copy approximately. Here we construct two types of a ``universal quantum deletion machine'' which approximately deletes a copy such that the fidelity of deletion does not depend on the input state. The two types of universal quantum deletion machines are (1) a conventional deletion machine described by one unitary operator and (2) a modified deletion machine described by two unitary operators. Here it is shown that the modified deletion machine deletes a qubit with fidelity $3∕4$ , which is the maximum limit for deleting an unknown quantum state. In addition to this we also show that the modified deletion machine retains the qubit in the first mode with average fidelity 0.77 (approx.) which is slightly greater than the fidelity of measurement for two given identical states, showing how precisely one can determine its state [S. Massar and S. Popescu, Phys. Rev. Lett. 74, 1259 (1995)]. We also show that the deletion machine itself is input state independent, i.e., the information is not hidden in the deleting machine, and hence we can delete the information completely from the deletion machine.Suppose we are given two identical copies of an unknown quantum state and we wish to delete one copy from among the given two copies. The quantum no-deletion principle restricts us from perfectly deleting a copy but it does not prohibit us from deleting a copy approximately. Here we construct two types of a ``universal quantum deletion machine'' which approximately deletes a copy such that the fidelity of deletion does not depend on the input state. The two types of universal quantum deletion machines are (1) a conventional deletion machine described by one unitary operator and (2) a modified deletion machine described by two unitary operators. Here it is shown that the modified deletion machine deletes a qubit with fidelity $3∕4$, which is the maximum limit for deleting an unknown quantum state. In addition to this we also show that the modified deletion machine retains the qubit in the first mode with average fidelity 0.77 (approx.) which is slightly greater than the fidelity of measurement for two given identical states, showing how precisely one can determine its state [S. Massar and S. Popescu, Phys. Rev. Lett. 74, 1259 (1995)]. We also show that the deletion machine itself is input state independent, i.e., the information is not hidden in the deleting machine, and hence we can delete the information completely from the deletion machine.

arXiv:quant-ph/0510182Physical Review ANov 18, 200514 citations

3∕4

, which is the maximum limit for deleting an unknown quantum state. In addition to this we also show that the modified deletion machine retains the qubit in the first mode with average fidelity 0.77 (approx.) which is slightly greater than the fidelity of measurement for two given identical states, showing how precisely one can determine its state [S. Massar and S. Popescu, Phys. Rev. Lett. 74, 1259 (1995)]. We also show that the deletion machine itself is input state independent, i.e., the information is not hidden in the deleting machine, and hence we can delete the information completely from the deletion machine.