QCA Structures	Previous Structures			Proposed Structures
QCA Structures	Complexity	Area	Latency	Figures	Complexity	Area	Latency
XOR gate [15]	34 cells	0.06 µm²	1	Figure 4(a)	30 cells	0.03 µm²	0.5
Half adder [29]	77 cells	83160 nm²= 0.08 µm²	1	Figure 5(a)	46 cells	0.05 µm²	0.5
Half adder [29]	105 cells	108000 nm²= 0.10 µm²	1	Figure 6(a)	22 cells	0.03 µm²	1
Full adders [30]	92 cells	0.20 µm²	Not shown	Figure 7(a)	120cells	0.15 µm²	2.5
[31]	145 cells	0.17 µm²	5	Figure 8(a)	69 cells	0.08 µm²	1
[32]	220 cells	0.36 µm²	3	Figure 9(a)	123 cells	0.14 µm²	2
[33]	180 cells	0.22 µm²	4
[34]	150 cells	2.25 µm²	2.25