Figure 1

(a) Atomic-vapor cell is placed inside the PPR. The geometrical details are presented by its specific geometry parameters which is \(l_{\mathrm{up}} = l_{\mathrm{down}} =l_{\mathrm{r}}= 19.2\) mm in length, \(d = 0.01\) mm in thickness, \(h = 10\text{ mm}\) in width, \(g = 4\text{ mm}\), \(w_{\mathrm{r}} = 10\text{ mm}\) in height, and \(w_{\mathrm{up}} =w_{\mathrm{down}}= 3\text{ mm}\) in length. (b) Equivalent lumped LC circuit representation. (c) Contribution of the electric field E along the curve ABCD corresponding to curvilinear coordinate along half PPR with AB = 3 mm, BC = 19.2 mm, CD = 5 mm. Theoretical results corresponding to red dashed line, FDTD simulations corresponding to black line.(d-f) \(x_{\mathrm{r}}\)O\(y_{ \mathrm{r}}\), \(x_{\mathrm{r}}\)O\(z_{\mathrm{r}}\), \(z_{\mathrm{r}}\)O\(y_{ \mathrm{r}}\) E-field strength distribution, respectively