Cavity-enhanced detection of spin polarization in a microfabricated atomic vapor cell

We demonstrate continuous Pound-Drever-Hall (PDH) nondestructive monitoring of the electron spin polarization of an atomic vapor in a microfabricated vapor cell within an optical resonator. The two-chamber silicon and glass cell contains 87Rb and 1.3¿amg of N2 buffer gas, and is placed within a plan...

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Detalles Bibliográficos
Autores: Hernandez Ruiz, María, Ma, Yintao, Medhat Abdelhadi Abdelaal, Hana Mahmoud, Mazzinghi, Chiara, Lucivero, Vito Giovanni, Mitchell, Morgan W.
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:dnet:upcommonspor::8d623a44c321b77a73cba59707413973
Acceso en línea:https://hdl.handle.net/2117/462433
https://dx.doi.org/10.1103/PhysRevApplied.21.064014
Access Level:acceso abierto
Palabra clave:Pound-Drever-Hall spectroscopy
Atomic spin polarization
Optical resonator sensing
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica::Fotònica
Descripción
Sumario:We demonstrate continuous Pound-Drever-Hall (PDH) nondestructive monitoring of the electron spin polarization of an atomic vapor in a microfabricated vapor cell within an optical resonator. The two-chamber silicon and glass cell contains 87Rb and 1.3¿amg of N2 buffer gas, and is placed within a planar optical resonator formed by two mirrors with dichroic dielectric coatings to resonantly enhance the coupling to phase-modulated probe light near the ¿2 line at 780¿nm. We describe the theory of signal generation in this system, including the spin-dependent complex refractive index, cavity optical transfer functions, and PDH signal response to spin polarization. We observe cavity transmission and PDH signals across approximately 200¿GHz of detuning around the atomic resonance line. By resonant optical pumping on the 795-nm ¿1 line, we observe spin-dependent cavity line shifts, in good agreement with theory. We use the saturation of the line shift versus optical pumping power to calibrate the number density and efficiency of the optical pumping. In the unresolved sideband regime, we observe quantum noise limited PDH readout of the spin polarization density, with a flat noise floor of 9×109 spins cm-3 Hz-1/2 for frequencies above 700¿Hz. We note possible extensions of the technique.