Rydberg Quantum Gates Free from Blockade Error

TL;DR

This paper introduces a new Rydberg-based quantum gate design that eliminates blockade errors, enabling faster and more accurate quantum operations by utilizing Rydberg energy shifts instead of blockade effects.

Contribution

The authors propose a novel Rydberg quantum gate that avoids blockade errors using energy shifts, improving fidelity and speed over previous blockade-based schemes.

Findings

Achieves blockade-error-free quantum gates.

Operates on a 0.1 microsecond timescale or faster.

Uses Rydberg energy shifts to realize generalized Rabi frequencies.

Abstract

Accurate quantum gates are basic elements for building quantum computers. There has been great interest in designing quantum logic gates by using blockade effect of Rydberg atoms recently. The fidelity and operation speed of these gates, however, are fundamentally limited by an intrinsic blockade error. Here we propose a type of quantum gates, which are based on Rydberg blockade effect, yet free from any blockade error. In contrast to the "blocking" method in previous schemes, we use Rydberg energy shift to realize a rational generalized Rabi frequency so that a $\pi$ phase for one input state of the gate emerges. This leads to an accurate Rydberg quantum logic gate that can operate on a 0.1-$\mu s$ timescale or faster because it works by a Rabi frequency which is comparable to the blockade shift.