Export citation

Export citation

Choose format for download:

Download Citation
  • Letter

Pair-condensation peak in radio-frequency dimer-projection spectroscopy of a unitary Fermi gas

Zhixiu Peng and Zhenhua Yu*

  • Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing, School of Physics and Astronomy, Sun Yat-Sen University (Zhuhai Campus), Zhuhai, Guangdong 519082, China and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-Sen University (Guangzhou Campus), Guangzhou, Guangdong 510275, China

  • *Contact author: yuzhh5@mail.sysu.edu.cn

Phys. Rev. A 114, L041301 – Published 5 October, 2026

DOI: https://doi.org/10.1103/5sk2-ws59

Abstract

Radio-frequency dimer-projection spectroscopy has recently emerged as a powerful probe of strongly interacting Fermi gases, yet its frequency-resolved spectrum remains largely unexplored. Here we show that the spectrum exhibits two qualitatively distinct features: a broad quasiparticle continuum governed by fermionic pairing and a sharp pair-condensation peak arising from the coherent projection of condensed Cooper pairs onto the final-state dimer. To reveal this physics, we develop a point-dimer approximation that exploits the separation between the molecular and many-body length scales and expresses the radio-frequency response directly in terms of pair correlations in the initial many-body state. Within the BCS mean-field theory, we derive the frequency-dependent spectrum, identify the microscopic transfer processes underlying its structure, and show that the continuum possesses a threshold determined by the superfluid gap. Our theory establishes radio-frequency dimer-projection spectroscopy as a unified probe of short-range correlations, fermionic pairing, and long-range coherence in strongly interacting Fermi gases.

Physics Subject Headings (PhySH)

Authorization Required

We need you to provide your credentials before accessing this content.

Supplemental Material (Subscription Required)

References (Subscription Required)

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation