Figure 4.

(a) The band gap, min⁡[ω_N/2+1⁻² − ω_N/2⁻²] as a function of the tolerance values for a 3 × 3 × 3 super cell. N is number of total bands for the 3 × 3 × 3 super cell. The parameters are the same as Figure 3 without considering the fabrication errors. After taking the fabrication errors into consideration, we repeat 100 times calculations for each tolerance values. The numerical results show that the gap equals zero; i.e., Weyl points exist for the tolerance values less than 30%. Exceeding this value, the gap opens by the fabrication errors. (b) The band dispersions along the k line crossing two Weyl points for a 3 × 3 × 3 super cell with ±20% tolerance values on the capacitors.