Figure 1

(a) Quantum coherence versus temperature for different J _z , for \(\overrightarrow{D}=\mathrm{(0},\,0,\,\mathrm{1)}\), J _x  = −1 and J _y  = −0.5. (b) Quantum coherence versus J _z for different temperatures for \(\overrightarrow{D}=\mathrm{(0,}\,\mathrm{0,}\,\mathrm{1)}\), J _x  = −1 and J _y  = −0.5. (c) Quantum coherence versus J _x for different temperatures for \(\overrightarrow{D}=\mathrm{(0,\; 0,\; 1)}\), J _z  = −1 and J _y  = −0.5. (d) Quantum coherence versus D _z for different temperatures when J _z  = 0.2 J _x  = −1 and J _y  = −0.5.