All-optical reversible logic gate via adiabatic population transfer

TL;DR

This paper proposes and theoretically analyzes all-optical implementations of three-bit and four-bit Toffoli gates using adiabatic population transfer techniques like STIRAP in multi-level quantum systems, ensuring correct logic operation.

Contribution

It introduces novel all-optical methods for implementing reversible Toffoli gates with adiabatic population transfer, expanding quantum logic gate design.

Findings

Successful theoretical demonstration of three-bit and four-bit Toffoli gates

Derivation of conditions for adiabatic evolution and robustness

Validation of correct truth table implementation

Abstract

The Toffoli gate is an essential logic element, which permits implementation of a reversible processor. It is of relevance both for classical as well as quantum logics. We propose and theoretically study all-optical implementations of three-bit and four-bit Toffoli gates by application of adiabatic population transfer techniques. For a three-bit Toffoli gate we use variants of stimulated Raman adiabatic passage (STIRAP) processes in a $\Lambda$-type level scheme, driven by two laser pulses at sufficiently large detunings. For the implementation of a four-bit Toffoli gate, we apply reversible adiabatic population transfer in five-level quantum systems, interacting with three laser pulses. We demonstrate correct all-optical implementation of the truth table of three-bit and four-bit Toffoli gates. Moreover, we derive conditions for adiabatic evolution of the population dynamics and robust operation of the gates.