Observation of Zeeman shift in the rubidium D2 line using an optical nanofiber in vapor

We report on the observation of a Zeeman shift (order of 100 MHz) of the Doppler-broadened D2 transition of both 85Rb and 87Rb isotopes via transmission through a 400 nm diameter optical nanofiber in the presence of a DC magnetic field. Linearly-polarized light propagating in the nanofiber is analyzed as a superposition of two orthogonally circularly polarized orientations, σ+ and σ-. In the absence of the magnetic field, the absorption of these polarizations by the atomic vapor, via the evanescent field at the waist of the nanofiber, is degenerate. When a weak magnetic field is applied parallel to the propagating light, this degeneracy is lifted and relative shifts in the resonance frequencies are detected. Typical linear shift rates of 1.6 MHz/G and -2.0 MHz/G were observed. We also demonstrate a dichroic atomic vapor laser lock line shape by monitoring the real-time subtraction of the two magnetically-shifted absorption spectra. This is particularly interesting for magneto-optical experiments as it could be directly implemented for diode laser frequencystabilization.

[1]  S. Cornish,et al.  DAVLL lineshapes in atomic rubidium , 2007 .

[2]  J. Kerckhoff,et al.  A frequency stabilization method for diode lasers utilizing low-field Faraday polarimetry , 2005 .

[3]  Laura Russell,et al.  Sub-Doppler temperature measurements of laser-cooled atoms using optical nanofibres , 2011 .

[4]  Valeriy V. Yashchuk,et al.  Laser frequency stabilization using linear magneto-optics , 2000 .

[5]  G S Pati,et al.  Observation of nonlinear optical interactions of ultralow levels of light in a tapered optical nanofiber embedded in a hot rubidium vapor. , 2008, Physical review letters.

[6]  Cai,et al.  Observation of critical coupling in a fiber taper to a silica-microsphere whispering-gallery mode system , 2000, Physical review letters.

[7]  Laura Russell,et al.  Spectral distribution of atomic fluorescence coupled into an optical nanofibre , 2009 .

[8]  Wei Jin,et al.  Evanescent-wave photoacoustic spectroscopy with optical micro/nano fibers. , 2012, Optics letters.

[9]  Richard J. Black,et al.  Tapered single-mode fibres and devices. I. Adiabaticity criteria , 1991 .

[10]  Jonathan Ward,et al.  Thermo-Optical Tuning of Whispering Gallery Modes in Erbium:Ytterbium Doped Glass Microspheres to Arbitrary Probe Wavelengths , 2012 .

[11]  A Rauschenbeutel,et al.  Dispersive optical interface based on nanofiber-trapped atoms. , 2011, Physical review letters.

[12]  M. Shahriar,et al.  Ultra-low power, Zeno effect based optical modulation in a degenerate V-system with a tapered nano fiber in atomic vapor. , 2011, Optics express.

[13]  V. B. Tiwari,et al.  Laser frequency stabilization using Doppler-free bi-polarization spectroscopy , 2006 .

[14]  Síle Nic Chormaic,et al.  Manifestation of the van der Waals surface interaction in the spontaneous emission of atoms into an optical nanofiber , 2010 .

[15]  Síle Nic Chormaic,et al.  Tapered optical fibers as tools for probing magneto-optical trap characteristics. , 2009, The Review of scientific instruments.

[16]  M. Takiguchi,et al.  Saturated absorption spectroscopy of acetylene molecules with an optical nanofiber. , 2011, Optics letters.

[17]  Yongmin Jung,et al.  Polarization-maintaining optical microfiber. , 2010, Optics letters.

[18]  T B Pittman,et al.  Observation of two-photon absorption at low power levels using tapered optical fibers in rubidium vapor. , 2010, Physical review letters.

[19]  Fam Le Kien,et al.  Optical nanofiber as an efficient tool for manipulating and probing atomic Fluorescence. , 2007, Optics express.

[20]  Carter F. Hand,et al.  Frequency-stabilized diode laser with the Zeeman shift in an atomic vapor. , 1998, Applied optics.