Visualization of spin-polarized electronic states by imaging-type spin-resolved photoemission microscopy

TL;DR

This paper introduces an imaging-type spin-resolved photoemission microscopy (iSPEM) with 420 nm resolution, enabling detailed visualization of spin-polarized electronic states in microscopic materials and devices, significantly advancing the field.

Contribution

The development of iSPEM with high spatial resolution and multi-channel detection offers a new tool for investigating spin-polarized states at sub-micrometer scales.

Findings

Achieved 420 nm spatial resolution in spin-resolved imaging.

Reduced data acquisition time by four orders of magnitude.

Enabled analysis of spin states in microscopic and device-scale materials.

Abstract

Harnessing electron spin is crucial in developing energy-saving and high-speed devices for the next generation. In this scheme, visualizing spin-polarized electronic states aids in designing and developing new materials and devices. Spin-resolved photoemission spectroscopy provides information on the spin-polarized electronic states. To investigate the spin-polarized electronic states in microscopic materials and devices, spin-resolved photoemission spectroscopy requires spatial resolution in a sub-micrometer scale. Here we show the imaging-type spin-resolved photoemission microscopy (iSPEM) with an ultraviolet laser developed at the National Institutes for Materials Science (NIMS). Our iSPEM achieves a spatial resolution of 420 nm, drastically improving by more than an order of magnitude compared to conventional spin-resolved photoemission spectroscopy instruments. Besides, the multi-channel spin detector significantly reduces the data acquisition time by four orders of magnitude compared to the conventional instruments. The iSPEM machine elucidates the spin-polarized electronic states of sub-micrometer scale materials, polycrystals, device structure samples, and so on, which have yet to be the target of conventional spin-resolved photoemission spectroscopy.