Quantum phase transition modulation in an atomtronic Mott switch

TL;DR

This paper proposes a 1D Mott switch using ultracold Bose gases in optical lattices, demonstrating a conductance transition controlled by lattice intensity, with potential applications in atomtronics.

Contribution

It introduces a novel atomtronic Mott switch design and characterizes its operation using time-evolving block decimation simulations.

Findings

Successful modulation of conductance via lattice tuning

Demonstration of Fock state transmission and fidelity control

Analysis of superfluid fragments through $g^{(2)}$ correlations

Abstract

Mott insulators provide stable quantum states and long coherence times to due to small number fluctuations, making them good candidates for quantum memory and atomic circuits. We propose a proof-of-principle for a 1D Mott switch using an ultracold Bose gas and optical lattice. With time-evolving block decimation simulations -- efficient matrix product state methods -- we design a means for transient parameter characterization via a local excitation for ease of engineering into more complex atomtronics. We perform the switch operation by tuning the intensity of the optical lattice, and thus the interaction strength through a conductance transition due to the confined modifications of the "wedding cake" Mott structure. We demonstrate the time-dependence of Fock state transmission and fidelity of the excitation as a means of tuning up the device in a double well and as a measure of noise performance. Two-point correlations via the $g^{(2)}$ measure provide additional information regarding superfluid fragments on the Mott insulating background due to the confinement of the potential.