Amplification of quadratic Hamiltonians

TL;DR

This paper introduces Hamiltonian amplification (HA), a method to speed up quantum dynamics in continuous variable systems using local squeezing, even with limited system knowledge, and combines it with noise suppression techniques.

Contribution

The paper presents a novel Hamiltonian amplification technique for continuous variable systems that does not require detailed system knowledge and can be combined with dynamical decoupling.

Findings

HA can amplify unknown or noisy couplings and frequencies.

Combining HA with dynamical decoupling suppresses environmental noise.

Significant reduction in gate times for cavity resonator qubits.

Abstract

Speeding up the dynamics of a quantum system is of paramount importance for quantum technologies. However, in finite dimensions and without full knowledge of the details of the system, it is easily shown to be impossible. In contrast we show that continuous variable systems described by a certain class of quadratic Hamiltonians can be sped up without such detailed knowledge. We call the resultant procedure Hamiltonian amplification (HA). The HA method relies on the application of local squeezing operations allowing for amplifying even unknown or noisy couplings and frequencies by acting on individual modes. Furthermore, we show how to combine HA with dynamical decoupling to achieve amplified Hamiltonians that are free from environmental noise. Finally, we illustrate a significant reduction in gate times of cavity resonator qubits as one potential use of HA.