Cooper quartets in interacting hybrid superconducting systems

Abstract

Cooper quartets represent exotic fermion aggregates describing correlated matter at the basis of charge-$4e$ superconductivity and offer a platform for studying four-body interactions, of interest for topologically protected quantum computing, nuclear matter simulations, and more general strongly correlated matter. Focusing on solid-state systems, we show how to quantum design Cooper quartets in a double-dot system coupled to ordinary superconducting leads through the introduction of an attractive interdot interaction. A fundamentally novel, maximally correlated double-dot ground state, in the form of a superposition of vacuum $|0⟩$ and four-electron state $|4e⟩$, emerges as a narrow resonance in a many-body quartet correlator that is accompanied by negligible pair correlations and features a rich phenomenology. The system represents an instance of correlated Andreev matter and the results open the way to the exploration of interaction effects in hybrid superconducting devices, and the study of novel correlated states of matter with ingredients available in a quantum solid-state laboratory.

6 pages, 4 figures

References in corpus (15)

• Simulated Quantum Computation of Molecular Energies
• Theory of Intertwined Orders in High Temperature Superconductors
• A superconductor to superfluid phase transition in liquid metallic hydrogen
• Two-Dimensional Superconducting Fluctuations in Stripe-Ordered La(1.875)Ba(0.125)CuO(4)
• Charge $4e$ superconductivity from pair density wave order in certain high temperature superconductors
• Alpha-particle condensation in 16O via a full four-body OCM calculation
• Competing orders in one dimensional spin 3/2 fermionic systems
• Electron Attraction Mediated by Coulomb Repulsion
• Photon mediated interaction between distant quantum dot circuits
• Production of non-local quartets and phase-sensitive entanglement in a superconducting beam splitter
• Voltage-induced Shapiro steps in a superconducting multi-terminal structure
• Quartets and the Current-Phase Structure of a Double Quantum Dot Superconducting Bijunction at Equilibrium
• Charge-4$e$ Superconductivity in a Hubbard model
• Hidden symmetry in interacting-quantum-dot-based multi-terminal Josephson junctions
• Quartet Tomography in Multiterminal Josephson Junctions

Cited by in corpus (4)

• The hybrid Josephson rhombus: A superconducting element with tailored current-phase relation
• Double-quantum-dot Andreev molecules: Phase diagrams and critical evaluation of effective models
• Vestigial $d$-wave charge-$4e$ Superconductivity from Bidirectional Pair Density Waves
• Families of $d=2$ 2D subsystem stabilizer codes for universal Hamiltonian quantum computation with two-body interactions