Tunable Sideband Sources

The invention of Gas Discharge [1].

Figure: Laser Sideband Source.

shows an example of the structure of the 111 - 000 transition of the NH2 free radical near 960 GHz [8].

Figure: Laser Sideband Source.

Figure: NH2 Rotational Transition.
The 111-000 rotational transition of the
NH2 free radical.

Because the frequency of the FIR gas lasers can vary with operating conditions by 1 - 5 MHz, for good spectroscopic accuracy provision to stabilize the laser frequency is ordinarily required. A recent example is shown in

Figure: Frequency Stabilized Laser Sideband
Source.

shows an example of the spectra obtained with this system. There exists a powerful alternative to the generation of tunable sidebands from FIR lasers by the electronic methods just described: The tuning of the molecular resonances to the fixed frequencies of the FIR lasers by means of large electric (LER) or magnetic (LMR) fields [9].

Figure: Frequency Stabilized Laser Sideband
Source.

Figure: DSSD Band Head. A portion of the band head of the
fQ13 of the slightly asymmetric internal rotor DSSD.

References

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