1 / 6

Simplest interrogation scheme for the two-photons transition

Simplest interrogation scheme for the two-photons transition. Two-photons Ramsey spectroscopy. Raby frequency: E: electric field strength; R i,j : i  j transition probability; dw : laser detuning; P : power in W; w : waist radius in m To have a π/2 pulse:

snowy
Télécharger la présentation

Simplest interrogation scheme for the two-photons transition

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Simplest interrogation scheme for the two-photons transition

  2. Two-photons Ramsey spectroscopy • Raby frequency: • E: electric field strength; Ri,j: ij transition probability; • dw: laser detuning; P: power in W; w: waist radius in m • To have a π/2 pulse: • t: interaction time; v: atomic velocity in m/s • This is possible with v = 20 m/s and P = 50 W (laser power: 0.5 W, cavity enhancement factor: 100) using a waist radius of 0.5 mm

  3. Measurement of the one-photon transition probability • The transition rate Aki for the intercombination line @ 657.3 nm is well known (2900 s-1) • Simultaneous measurement of the integrated absorption coefficient a(n) @ 457.5 nm and 657.3 nm • Cell transmission: • L: length of the absorbing vapor; N: atomic density; • g(n): normalized lineshape; gi: level degeneracy

  4. Apparatus for measuring the E2 transition rate • Ti:Sa laser: 400 mW CW @ 915 nm • SHG with a KNbO3 crystal: 300 mW @ 457.5 nm • ECDL: 10 mW CW @ 657.3 nm • Frequency calibration: two Fabry-Pérot resonators • FSR 300 MHz • Absorption cell • length 0.6 m; diameter 2.5 cm; temperature 650÷700 °C

  5. Data analysis • Fit assuming a pure Doppler line broadening • Doppler linewidth ≈ 2 GHz • buffer gas (Ar) pressure: 10÷20 Pa • broadening coefficient ≈ 100÷150 kHz/Pa • Isotopic structure • most abundant isotopes: 40Ca (96.9%), 44Ca (2%), 42Ca (0.6%) • G(n) normalized Gaussian function

  6. Experimental apparatusfor measuring the E2transition rate

More Related