Atomic Ramsey interferometry with S- and D-band in a triangular optical lattice

TL;DR

This paper introduces a novel two-dimensional Ramsey interferometer using Bloch states in S- and D-band of a triangular optical lattice, enhancing coherence time and enabling advanced quantum simulations.

Contribution

It develops the first Ramsey interferometry with external Bloch states in a 2D coupled lattice, utilizing shortcut methods for pulse construction and echo pulses for coherence enhancement.

Findings

Clear Ramsey fringes observed

Decoherence mechanisms analyzed

Coherence time significantly improved with echo pulse

Abstract

Ramsey interferometers have wide applications in science and engineering. Compared with the traditional interferometer based on internal states, the interferometer with external quantum states has advantages in some applications for quantum simulation and precision measurement. Here, we develop a Ramsey interferometry with Bloch states in S- and D-band of a triangular optical lattice for the first time. The key to realizing this interferometer in two-dimensionally coupled lattice is that we use the shortcut method to construct $\pi/2$ pulse. We observe clear Ramsey fringes and analyze the decoherence mechanism of fringes. Further, we design an echo $\pi$ pulse between S- and D-band, which significantly improves the coherence time. This Ramsey interferometer in the dimensionally coupled lattice has potential applications in the quantum simulations of topological physics, frustrated effects, and motional qubits manipulation.