ESR intensity and the Dzyaloshinsky-Moriya interaction of the nanoscale molecular magnet V${}_{15}$

The intensity of electron spin resonance (ESR) of the nanoscale molecular magnet ${\mathrm{V}}_{15}$ is studied. We calculate the temperature dependence of the intensity at temperatures from high to low. In particular, we find that the low-temperature ESR intensity is significantly affected by the Dzyaloshinsky-Moriya interaction.

Figure 1

Schematic picture of ${\mathrm{V}}_{15}$.

Figure 2

Heisenberg interactions between the spins.

Figure 3

The $D_3$ symmetry of ${\mathrm{V}}_{15}$.

Figure 4

The temperature dependencies of the intensity for $\mathbf{H}\left|\right|z$ and $H=2\mathrm{T}$ and the experimental intensity.

Figure 5

The temperature dependence of the intensity for $\mathbf{H}\left|\right|z$ and $H=4\mathrm{T}$.

Figure 6

The temperature dependence of the intensity for $\mathbf{H}\left|\right|z$ and $H=2\mathrm{T}$.

Figure 7

(a) The lowest eight levels of ${\mathrm{V}}_{15}$ as a function of $\mathbf{H}\left|\right|z$. (b) Magnified figure near $3\mathrm{T}$.

Figure 8

The intensity ratios of ${\mathrm{V}}_{15}$ as a function of the temperature. The intensity ratios without the DMI are also shown for comparison.

Figure 9

(a) Intensity ratios of ${\mathrm{V}}_{15}$ as a function of temperature for various fields. (b) Intensity ratios without the DMI.

Figure 10

Energy levels of the triangle model as a function of the field $H$.