Periodic drive induced unconventional superconductivity in a half-filled system

TL;DR

This paper proposes a novel non-equilibrium Floquet engineering approach to induce and stabilize unconventional d-wave superconductivity in a half-filled system, bypassing doping and disorder.

Contribution

It introduces a high-frequency drive method to transform a Mott insulator into a d-wave superconductor by manipulating hopping parameters and magnetic order.

Findings

High-frequency drive induces strong correlations via hopping renormalization.

Staggered hoppings frustrate antiferromagnetic order, enabling pairing.

Superconductivity remains stable over exponentially long timescales.

Abstract

The non-equilibrium control of electronic properties has emerged as a transformative paradigm for engineering novel quantum phases. The most intriguing example of such a phase is light-induced superconductivity (SC) in non-superconducting materials. However, realizing unconventional SC at commensurate half-filling remains a formidable challenge even in non-equilibrium, as the regime is typically dominated by the robust stability of the antiferromagnetic (AFM) Mott insulating (MI) state. Here, we provide a novel non-equilibrium route to realize unconventional d-wave SC in a half-filled system through Floquet engineering. We analyze the periodically driven Fermi-Hubbard model on a bipartite lattice and demonstrate that a high-frequency drive can transform a weakly interacting insulator into a regime of strong correlations by the drive-induced renormalization of nearest-neighbor hopping. Furthermore, the drive induces staggered higher range hoppings that can frustrate the AFM order while simultaneously generate staggered potential that lifts the kinetic constraints inherent to the half-filled system, fostering the charge dynamics required to stabilize d-wave pairing against the competing AFM state. The resulting SC phase is protected by high-frequency prethermalization, maintaining stability over timescales exponentially large in the drive frequency. This protocol circumvents the need for chemical doping, offering a 'disorder-free' alternative for realizing unconventional pairing with direct applications in optimizing the performance of superconducting quantum computers, qubit arrays and other upcoming quantum technologies.