Single crystal studies and electronic structure investigation of a room-temperature semiconductor NaMnAs

TL;DR

This study synthesizes and characterizes single-crystal NaMnAs, confirming its antiferromagnetic semiconductor properties at room temperature through experimental and theoretical methods.

Contribution

First comprehensive synthesis and electronic structure analysis of single-crystal NaMnAs, including experimental validation and theoretical modeling.

Findings

NaMnAs is confirmed as a room-temperature antiferromagnetic semiconductor.

Optical transmittance aligns with theoretical predictions.

Néel temperature determined and supported by Monte Carlo simulations.

Abstract

We report synthesis of single crystalline NaMnAs, confirm its antiferromagnetic order and characterise the sample by photoemission spectroscopy. The electronic structure was studied using optical transmittance, x-ray and ultraviolet spectroscopy and by theoretical modeling using local density approximation (LDA) extended to LDA+U when Heisenberg model parameters were determined. Optical transmittance measurement have confirmed the theoretical predictions that NaMnAs is a semiconductor. Also the N\'eel temperature was closer determined for the first time from temperature dependence of magnetization, in agreement with our Monte Carlo simulations.