Simulating Dirac equation with Josephson junction circuits

TL;DR

This paper proposes a superconducting circuit scheme to simulate Dirac equations in various dimensions, enabling experimental study of relativistic quantum phenomena like Zitterbewegung with longer decoherence times.

Contribution

It introduces a novel superconducting qubit-based method to simulate Dirac equations across multiple dimensions, facilitating experimental exploration of relativistic quantum effects.

Findings

Decoherence time exceeds transition time with proper parameters.

Simulation scheme applicable to 3+1, 2+1, 1+1 dimensions.

Potential to observe Zitterbewegung and electron/neutrino dynamics.

Abstract

We propose a scheme for simulating 3+1, 2+1, 1+1 Dirac equation for a free spin-1/2 particle with superconducting josephson circuits consisting of five qubits, four qubits, two qubits respectively. In 3+1D and 2+1D, the flux qubit1 driven by a resonant pulse is in the superposition state of its own two eigenstatesis, and it is used as a bus to induce the (blue)red-sideband excitation consisting of a magnetic pulse acting resonantly on two levels of the flux qubit2 and the energy levels of one phase qubit, which yields two (Anti)Jaynes-Cummings interactions with one driving pulse and reduces the damage of the driving pulses to the system consequently. Numerical results show that decoherence time is several times longer than transition time supposing set appropriate experimental parameters. Therefore experiments verifying the dynamics of electron and neutrino, such as Zitterberwung effect in 3+1, 2+1 and 1+1 dimensions, can be implemented by microelectronic chips composed of the qubits as artificial atoms.