Y. Millerioux

Optical frequency determination of the hyperfine components of the 5S12-5D32 two-photon transitions in rubidium

Abstract An absolute optical frequency measurement is made of the hyperfine components of the 5S 1 2 -5D 3 2 two-photon transitions in rubidium with an uncertainty of 1.3×10-11. This is carried out in a simple way by taking advantage of the near coincidence between the two-photon frequency at λ=778 nm in Rb and the frequency difference of two HeNe lasers, stabilized respectively to an iodine line at λ=633 nm and a methane transition at λ=3.39 μm used as reference. This measurement provides a new optical frequency reference in the visible range.

A CO2 to visible optical frequency synthesis chain: accurate measurement of the 473 THz HeNe/I2 laser

Abstract We have built an optical frequency synthesis chain starting from our laboratory-measured reference at 29 THz (CO 2 /OsO 4 laser) and we have measured the frequency of a HeNe laser locked on a hyperfine transition of iodine at 473 THz. The result of the measurement of the laser locked on the “f” component of the (127) R11-5 transition is v =473 612 353 586.9 ± 5 KHz. The given uncertainty (Δ v / v =1×10 -11 ) is 10 times better than the previous published measurement. It is only limited by the reproducibility of that standard laser. Our chain is potentially capable of measuring optical frequencies from the visible down to the near infrared range with an accuracy level of 10 -12 , which is presently limited by our reference accuracy.

Towards an accurate frequency standard at λ778 nm using a laser diode stabilized on a hyperfine component of the Doppler-free two-photon transitions in rubidium

Abstract Two systems are built in which a commercially available GaAlAs laser diode is stabilized on a hyperfine component of the 5S 1 2 −5D( 3 2 , 5 2 ) two-photon transitions in rubidium at λ=778 nm (v=385 THz). Some preliminary metrological results are presented. The frequency repeatability has been found to be of 200 Hz (5.2 parts in 1013) and a short-term frequency stability of 3×10-13/ τ /gt up to 2000 s is currently obtained.

Results from international comparisons at the BIPM providing a world-wide reference network of /sup 127/I/sub 2/ stabilized frequency-doubled Nd:YAG lasers

Frequency comparisons have been carried out between iodine-stabilized Nd:YAG lasers from the Bureau International des Poids et Mesures, the Bureau National de Metrologie-Institut National de Metrologie, the Czech Metrology Institute, the Centre for Metrology and Accreditation, and the National Metrology Institute of Japan/National Institute of Advanced Industrial Science and Technology. The comparison data of these lasers can now be linked to the results of recent absolute frequency measurements of lasers from different institutes.

Hyperfine structure of the 47R(9-2), 48P(11-3) and 48R(15-5) lines of 127I2 at 612 nm as secondary standards of optical frequency

A spectroscopic study of the 47R(9-2), 48P(11-3) and 48R(15-5) lines of the B-X electronic transition 127I2 iodine molecule at 612 nm was undertaken using a continuous-wave tunable dye laser. The uncertainty in the frequency interval measurements between the hyperfine components, of a few kHz, allows determination of the differences between constants of the four principal hyperfine interactions.

Performance of a GaAlAs laser diode stabilized on a hyperfine component of two-photon transitions in rubidium at 778 nm

The absolute frequency measurement of each hyperfine component of the 5S3/2 and 5S5/2 levels in rubidium was done at ENS more than one year ago using Ti-Sa lasers. We built two devices based on diode lasers to study some metrological properties. We measure the frequency differences between hyperfine components of the 5S5/2 level and we calculate the corresponding hyperfine constants. We also measure the frequency interval between the 5S3/2 and 5S5/2 levels using a Schottky diode. The measured stability in terms of Allan variance is 3*10-13t-1/2 up to 2000 s. The light shift is investigated and the difference between our two systems is 1.7 kHz. The repeatability of one system is better than 10-12 and will allow the absolute frequency measurement at this level via the LPTF frequency synthesis chain.

A potential new frequency/wavelength standard at 778 nm: Doppler free two-photon transitions in rubidium

We have stabilized two laser diodes on the hyperfine components of the 5D/sub 3/2/ and 5D/sub 5/2/ two-photon transitions in natural rubidium (v=385 THz). We have carefully investigated the metrological features of these devices. So far we obtain a frequency stability in terms of the Allan variance of 3.10/sup -13/./spl tau//sup - 1/2 / up to 2000 s and a frequency repeatability of the order of 10/sup -12/. The frequency difference between the two devices is 1.7 kHz under identical operating conditions.<<ETX>>

Results from international comparisons at the BIPM providing a world wide reference network of /sup 127/I/sub 2/-stabilized frequency-doubled Nd:YAG lasers

Summary form only given. Frequency comparisons of iodine-stabilized Nd:YAG lasers from the BIPM, the BNM-INM, the CMI, the MIKES, and the NMIJ/AIST have been made. The frequencies of these lasers can now be linked together with those of absolutely measured lasers from the JILA/NIST, the PTB and the ILP (Novosibirsk).

Absolute frequency measurement of a diode laser locked on a hyperfine component of 5S1/2-5D5/2 two-photon transitions of rubidium (lambda equals 778.1 nm, nu equals 385.3 THz)

A frequency chain, derived from the one used to measure the absolute frequency ((nu)

Towards a frequency measurement of the Rydberg constant using the 2S-8S and 2S-8D transitions of hydrogen

= 473 THz) of the He-Ne/I2 optical standard, is currently being implemented in order to measure the frequency of a diode laser stabilized on the two-photon transition of rubidium vapor. The measurement scheme is based on the comparison of the frequency of this near-IR potential secondary standard to the 13th harmonic frequency of the R(12)-CO2/OsO4 LPTF secondary standard at (nu) equals 29.096 THz. Recent results on the frequency synthesis are reported, enabling the testing of long-term stability of this Rb-locked system with respect to the IR reference standard.