近日，山西大学的董磊及其研究团队取得一项新进展。经过不懈努力，他们提出石英增强多外差共振光声光谱学技术。相关研究成果已于2024年3月22日在国际知名学术期刊《光：科学与应用》上发表。

在这项工作中，研究人员提出一种石英增强多外差共振光声光谱（QEMR-PAS）技术。该技术中，双梳的拍频响应频率被频率下转换到音频域，使得气体分子能够通过光声效应作为光声转换器，产生外差声波。与传统的双梳光谱学（DCS）相比，QEMR-PAS具有显著优势。传统的DCS依赖于波长相关的光接收器来检测光波，而QEMR-PAS则采用石英音叉（QTF）作为高Q声音换能器，并与相敏检测器协同工作。

这一组合使得该技术能够从多个外差声学音调中精确提取共振声音成分，从而实现了硬件配置的简化与成本降低。这种新颖的QEMR-PAS技术不仅实现了与波长无关的DCS气体传感检测，还展现出了卓越的性能。它提供了高达63dB的动态范围，显著的光谱分辨率达到了43MHz（或~0.3pm），以及卓越的噪声等效吸收系数5.99 × 10^-6cm^-1·Hz^-1/2。

据悉，双梳光谱学（DCS）现已扩展至覆盖所有波长的光，凭借其提供的超大动态范围和超高光谱分辨率的能力，使其在物理、化学、大气科学、空间科学以及医学等多个领域中都发挥着不可或缺的作用。

附：英文原文

Title: Quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy

Author: Wang, Jiapeng, Wu, Hongpeng, Sampaolo, Angelo, Patimisco, Pietro, Spagnolo, Vincenzo, Jia, Suotang, Dong, Lei

Issue&Volume: 2024-03-22

Abstract: The extension of dual-comb spectroscopy (DCS) to all wavelengths of light along with its ability to provide ultra-large dynamic range and ultra-high spectral resolution, renders it extremely useful for a diverse array of applications in physics, chemistry, atmospheric science, space science, as well as medical applications. In this work, we report on an innovative technique of quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy (QEMR-PAS), in which the beat frequency response from a dual comb is frequency down-converted into the audio frequency domain. In this way, gas molecules act as an optical-acoustic converter through the photoacoustic effect, generating heterodyne sound waves. Unlike conventional DCS, where the light wave is detected by a wavelength-dependent photoreceiver, QEMR-PAS employs a quartz tuning fork (QTF) as a high-Q sound transducer and works in conjunction with a phase-sensitive detector to extract the resonant sound component from the multiple heterodyne acoustic tones, resulting in a straightforward and low-cost hardware configuration. This novel QEMR-PAS technique enables wavelength-independent DCS detection for gas sensing, providing an unprecedented dynamic range of 63dB, a remarkable spectral resolution of 43MHz (or ~0.3pm), and a prominent noise equivalent absorption of 5.99 × 10^-6cm^-1·Hz^-1/2.

DOI: 10.1038/s41377-024-01425-1

Source: https://www.nature.com/articles/s41377-024-01425-1