Year: 2026
Type: article
Abstract: We propose and experimentally demonstrate a spectroscopic method, named full differential spectroscopy, that uses a single laser beam in retroreflected configuration to manipulate atomic dark states in a vapor cell. Conventional Doppler-free spectroscopy often suffers from limited performance due to the Doppler-broaden background. Here we show that by selectively coupling or decoupling the probe’s polarization components with the pump-induced dark state, we can simultaneously obtain both Doppler-free electromagnetically induced transparency and absorption. A differential signal, with enhanced Doppler-free amplitude and highly suppressed background and noise, is thus obtained. We systematically characterize how polarization angle and light power affect the resonance and noise properties. Using this approach, we stabilize a laser to a rubidium vapor cell, achieving a fractional frequency stability of 1.2 × 10 −13 at 1 s. These results demonstrate a simple, robust route to high-performance optical frequency references and may also benefit quantum sensing or high-resolution spectroscopy.
Source: Communications Physics
Institutions: Chinese Academy of Sciences, National Time Service Center, University of Chinese Academy of Sciences, Centre National de la Recherche Scientifique, Franche-Comté Électronique Mécanique Thermique et Optique - Sciences et Technologies, Université Marie et Louis Pasteur, École Nationale Supérieure de Mécanique et des Microtechniques, Centre for Quantum Technologies, Nanyang Technological University, University of Science and Technology of China, Suzhou Institute of Nano-tech and Nano-bionics
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,990
OpenAlex ID: W7214103209