Reversible logic

Templates for Positive and Negative Control Toffoli Networks

“…A gate is said to be self-reversible if the gate reverses its logic function [26]. The Toffoli gate is self-reversible.…”

“…The outputs of the second Toffoli gate are X = P, Y = Q, and Z = PQ ⊕ R, and the input of the second Toffoli gate is the output of the first Toffoli gate, that is, P = A, Q = B, and R = AB ⊕C. By substituting P, Q, R with A, B, C, we obtain X = A, Y = B, and Z = AB ⊕ AB ⊕C = C. A gate is said to be conservative if it preserves the number of logical ones in the input [26]. The Toffoli gate is not a conservative gate because the mapping changes from (111) to (110) as shown in Table 2.7(a).…”

Design of a 4-bit adder using reversible logic in quantum-dot cellular automata (QCA)

“…Apart from that, reversible logic technology [6] is also considered as an alternative technology to help improve the heat dissipation problem in CMOS devices. This is because most of current circuits are irreversible whereby input cannot be retrieved from the output since it is erased after every logical operation.…”

“…This is because most of current circuits are irreversible whereby input cannot be retrieved from the output since it is erased after every logical operation. Erasing the input information dissipates heat [6]. This process does not occur in reversible circuits which ideally reduces the heat dissipation problem in device.…”

Synthesis of reversible logic for nanoelectronic circuits

“…Mohan [4] states that 'the only way that nanotechnology can circumvent energy dissipation limits (and therefore can keep computer performance improving) is by wholeheartedly and thoroughly adopting reversible computing principles'. Reversible computing is not only useful in low-power classical computing [5][6][7][8][9], but also in quantum computing, as it has been proved [10] that a quantum computation is necessarily reversible.…”