Engineering Giant Nonlinearities in Quantum Nanosystems

TL;DR

This paper presents a method to engineer large nonlinearities in quantum resonators by tailoring auxiliary systems, enabling precise control and measurement of nonlinear quantum effects.

Contribution

It introduces a perturbative approach to design Hamiltonians for auxiliary systems that induce strong nonlinearities in mesoscopic quantum resonators, with explicit practical examples.

Findings

Successfully engineered x^4 potential in quantum resonators.

Realized Kerr nonlinearity with high accuracy.

Demonstrated applicability to two-qubit auxiliary systems.

Abstract

We describe a method to engineer giant nonlinearities in, and probes to measure nonlinear observables of, mesoscopic quantum resonators. This involves tailoring the Hamiltonian of a simple auxiliary system perturbatively coupled to the resonator, and has the potential to engineer a wide range of nonlinearities to high accuracy. We give a number of explicit examples, including a readily realizable two-qubit auxiliary system that creates an x^4 potential and a Chi^(3) (Kerr) nonlinearity, valid to fifth-order in the perturbative coupling.