Application of quantum scrambling in Rydberg atom on IBM quantum computer

TL;DR

This paper demonstrates a quantum circuit approach to measure quantum scrambling via OTOC in Rydberg atom systems, using IBM quantum computers to simulate Ising models and compare information scrambling in different initial states.

Contribution

It introduces a general interferometric quantum circuit to measure OTOC and applies it to Rydberg atom simulations on IBM quantum hardware, exploring quantum information scrambling.

Findings

Successfully measured OTOC in Rydberg atom simulation

Compared scrambling in product and entangled initial states

Proposed broader applications of the technique

Abstract

Quantum scrambling measured by out-of-time-ordered correlator (OTOC) has an important role in understanding the physics of black holes and evaluating quantum chaos. It is known that Rydberg atom has been a general interest due to its extremely favourable properties for building a quantum simulator. Fast and efficient quantum simulators can be developed by studying quantum scrambling in related systems. Here we present a general quantum circuit to theoretically implement an interferometric protocol which is a technique proposed to measure OTOC functions. We apply this circuit to measure OTOC and hence the quantum scrambling in a simulation of two spin Ising spin model for Rydberg atom. We apply this method to both initial product and entangled states to compare the scrambling of quantum information in both cases. Finally we discuss other constructions where this technique can be applied.