Frequency Measurement Of Tellurium Lines Near Calcium

We report measurement of frequencies of tellurium lines with respect to atomic calcium employing a 423nm commercial violet laser diode placed in an extended cavity. Doppler-free saturated absorption spectroscopy of molecular tellurium is performed on three lines, which are lower and higher in energy to the calcium 4s(2) S-1(0)-4(s)4(p) P-1(1) transition. The measured frequency difference of 717(13) MHz between the strong absorption line, #1508 in the tellurium atlas and the calcium transition is in agreement within 10% of the values available from literature. Wavenumbers of two new tellurium lines are derived from the measurement. In addition, spectroscopy and laser cooling and trapping of francium (n = 7) on the ns S-2(1/2)-(n + 1)p P-2(3/2) transition and spectroscopy of Te-2 lines near francium could be performed employing the 423 nm diode laser.