论文信息 - Direct determination of the Boltzmann constant by an optical method.

Direct determination of the Boltzmann constant by an optical method.

We have recorded the Doppler profile of a well-isolated rovibrational line in the nu(2) band of (14)NH(3). Ammonia gas was placed in an absorption cell thermalized by a water-ice bath. By extrapolating to zero pressure, we have deduced the Doppler width which gives a first measurement of the Boltzmann constant k(B) by laser spectroscopy. A relative uncertainty of 2 x 10(-4) has been obtained. The present determination should be significantly improved in the near future and contribute to a new definition of the kelvin.

[1] C. Bordé,et al. Vibrational dependence of the hyperfine quadrupole constant in 14NH3 observed by saturated absorption spectroscopy , 1977 .

[2] O. Pfister,et al. CO 2 -laser sideband spectroscopy at ultrahigh resolution , 1993 .

[3] A Amy-Klein,et al. Long-distance frequency dissemination with a resolution of 10(-17). , 2005, Physical review letters.

[4] Joachim Fischer,et al. Determination of the Boltzmann constant—status and prospects , 2006 .

[5] C. Daussy,et al. CO/sub 2/ laser stabilization to 0.1-Hz level using external electrooptic modulation , 1997 .

[6] D. Pritchard,et al. Penning Trap Measurements of the Masses of C133s, R87,85b, and N23a with Uncertainties ≤0.2 ppb , 1999 .

[7] L. Pendrill. Macroscopic and microscopic polarizabilities of helium gas , 1996 .

[8] A. Wicht,et al. A Preliminary Measurement of the Fine Structure Constant Based on Atom Interferometry , 2003 .

[9] François Nez,et al. Determination of the fine structure constant based on BLOCH oscillations of ultracold atoms in a vertical optical lattice. , 2006, Physical review letters.

[10] C. Bordé,et al. Base units of the SI, fundamental constants and modern quantum physics , 2005, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.