Observation of spin-space quantum transport induced by an atomic quantum point contact

TL;DR

This paper demonstrates spin-space quantum transport in a cold-atom system with ytterbium atoms, revealing impurity-induced transport phenomena that could advance atomtronics utilizing spin degrees of freedom.

Contribution

It introduces a novel quantum transport scheme using ytterbium atoms in a two-orbital optical lattice, focusing on spin-dependent interactions and impurity effects.

Findings

Observation of impurity-induced quantum transport in spin space

Control of spin current via localized impurities

Potential for atomtronic devices exploiting spin degrees of freedom

Abstract

Quantum transport is ubiquitous in physics. So far, quantum transport between terminals has been extensively studied in solid state systems from the fundamental point of views such as the quantized conductance to the applications to quantum devices. Recent works have demonstrated a cold-atom analog of a mesoscopic conductor by engineering a narrow conducting channel with optical potentials, which opens the door for a wealth of research of atomtronics emulating mesoscopic electronic devices and beyond. Here we realize an alternative scheme of the quantum transport experiment with ytterbium atoms in a two-orbital optical lattice system. Our system consists of a multi-component Fermi gas and a localized impurity, where the current can be created in the spin space by introducing the spin-dependent interaction with the impurity. We demonstrate a rich variety of localized-impurity-induced quantum transports, which paves the way for atomtronics exploiting spin degrees of freedom.