Digital quantum simulation of beam splitters and squeezing with IBM quantum computers

Abstract

We present results on the digital quantum simulations of beam-splitter and squeezing interactions. The bosonic Hamiltonians are mapped to qubits and then digitalized in order to implement them in the IBM quantum devices. We use error mitigation and postselection to achieve high-fidelity digital quantum simulations of single-mode and two-mode interactions, as evinced-where possible-by full tomography of the resulting states. We achieve fidelities above 90% in the case of single-mode squeezing with low squeezing values and ranging from 60% to 90% for large squeezing and in the more complex two-mode interactions.

Digital quantum simulation of quantum gravitational entanglement with IBM quantum computers

“…This could be necessary when considering extensions to higher number of modes or excitations or non-perturbative couplings. With the techniques developed in [10,15] it would be straightforward to address the extension to higher number of modes or allowed excitations. For instance, considering that state-of-the art quantum computers contain around 100 superconducting qubits, we could consider up to around 50 maximum excitations per mode, restricting ourselves to two harmonic oscillators.…”

“…In so doing, in [9] it is shown that if the harmonic oscillators are in fixed positions -static regime-then the leading interaction terms between them are two-mode squeezing and beam-splitter hamiltonians. This class of hamiltionians was already digitized in [10,15], giving rise to high-fidelity quantum simulations.…”

“…It consists in the combination of Trotter [11] and gatedecomposition techniques [12] with a boson-qubit mapping [13,14] in order to encode bosonic hamiltonians into a sequence of single-qubit and two-qubit gates. We have applied this scheme to the high-fidelity digital quantum simulation of paradigmatic quantum-optics interactions, such as beam-splitters or single-mode and two-mode squeezers [15].…”

Modeling Quantum Enhanced Sensing on a Quantum Computer

“…These experiments can be accomplished with minimal resources as the IBM Quantum Experience allows for free remote access. Additionally, students working independently for a class project could extend the techniques presented here to circuits with more than two qubits [4] in order to demonstrate different forms of entanglement and implement a variety of quantum squeezing techniques.…”

“…On the way to more advanced research goals, first generation quantum computers also serve as educational tools. The IBM Quantum Experience, for example, is an online quantum computing platform that provides the opportunity for students to interact with real quantum hardware [1][2][3][4].…”