“…The point defects include E′ centres, non-bridging oxygen hole centres (NBOHC), and divalent silicon with oxygen deficiency centres, i.e., SiODC (II). 7,[20][21][22][23] The few pulses limit the defect incubation process 28 (null formation of nanogratings, see Fig. 3a), being distributed within a narrow region with certain orientation, but still low anisotropic degree as will be shown below.…”