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 63 dB, a remarkable spectral resolution of 43 MHz (or ~0.3 pm), and a prominent noise equivalent absorption of 5.99 × 10^-6cm^-1·Hz^-1/2.

双梳光谱 (DCS) 扩展到所有波长的光，并具有提供超大动态范围和超高光谱分辨率的能力，使其在物理、化学、大气科学等领域的各种应用中极为有用、空间科学以及医学应用。在这项工作中，我们报告了石英增强多外差共振光声光谱（QEMR-PAS）的创新技术，其中双梳的拍频响应被频率下转换到音频域。这样，气体分子通过光声效应充当光声转换器，产生外差声波。与传统的 DCS（通过波长相关的光接收器检测光波）不同，QEMR-PAS 采用石英音叉 (QTF) 作为高Q声音传感器，并与相敏检测器结合使用以提取谐振声音组件来自多个外差声音，从而形成简单且低成本的硬件配置。这种新颖的 QEMR-PAS 技术能够实现与波长无关的气体传感 DCS 检测，提供前所未有的 63 dB 动态范围、43 MHz（或 ~0.3 pm）的卓越光谱分辨率以及 5.99 × 10 - 的显着噪声等效^吸收6厘米^-1 ·赫兹^-1/2。