# Quantum Discord, Thermal Discord, and Entropy Generation in the Minimum Error Discrimination Strategy

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## Abstract

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## 1. Introduction

## 2. Minimum Error Discrimination

## 3. Channel without Entanglement

## 4. Correlations between Alice and Bob

#### 4.1. Classical Correlations and Quantum Discord

#### 4.2. Thermal Discord

#### 4.3. Accessible Information and Optimum Success Probability

## 5. Conclusions

## Author Contributions

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**(

**a**) Accessible information and (

**b**) quantum discord, when $x=1$, as a function of the inner product $\alpha $ for ${\eta}_{0}=0.5$ (red line), ${\eta}_{0}=0.2$ (green line), and ${\eta}_{0}=0.05$ (black line).

**Figure 2.**(

**a**) Values of x that attain the thermal discord. (

**b**) Entropy generation in minimum error (ME) (solid line) and thermal discord (dashed line) as a function of the inner product $\alpha $ for: ${\eta}_{0}=0.49$ (red line), ${\eta}_{0}=0.2$ (green line), and ${\eta}_{0}=0.05$ (black line).

**Figure 3.**(

**a**) Average error probability in ME (solid lines) and for the case when the measurement base leads to the thermal discord (dashed lines). (

**b**) Accessible information versus average success probability in ME for ${\eta}_{0}=0.49$ (red line), ${\eta}_{0}=0.2$ (green line), and ${\eta}_{0}=0.05$ (black line).

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**MDPI and ACS Style**

Jiménez, O.; Solís-Prosser, M.A.; Neves, L.; Delgado, A.
Quantum Discord, Thermal Discord, and Entropy Generation in the Minimum Error Discrimination Strategy. *Entropy* **2019**, *21*, 263.
https://doi.org/10.3390/e21030263

**AMA Style**

Jiménez O, Solís-Prosser MA, Neves L, Delgado A.
Quantum Discord, Thermal Discord, and Entropy Generation in the Minimum Error Discrimination Strategy. *Entropy*. 2019; 21(3):263.
https://doi.org/10.3390/e21030263

**Chicago/Turabian Style**

Jiménez, Omar, Miguel Angel Solís-Prosser, Leonardo Neves, and Aldo Delgado.
2019. "Quantum Discord, Thermal Discord, and Entropy Generation in the Minimum Error Discrimination Strategy" *Entropy* 21, no. 3: 263.
https://doi.org/10.3390/e21030263