Broadband phase-modulated Fourier transform spectroscopy

A system for analyzing a sample using spectroscopy, comprising:

• a laser configured to generate a pulsed light beam;
• a beamsplitter configured to receive the pulsed light beam from the laser and split the pulsed light beam into two light paths;
• a first modulator disposed in a first light path of the two light paths and operates to phase modulate the pulsed light beam therein at a first frequency;
• a second modulator disposed in a second light path of the two light paths and operates phase modulate the pulsed light beam therein at a second frequency which differs from the first frequency;
• a first continuum generator disposed on the first light path downstream from the first modulator and operates to spectrally broaden the pulsed light beam;
• a second continuum generator disposed on the second light path downstream from the second modulator and operates to spectrally broadening the pulsed light beam;
• a delay mechanism disposed in the second light path downstream from the second continuum generator and operates to delay the pulsed light beam;
• a beam combiner configured to receive the pulsed light beam from the first continuum generator and the second continuum generator and operates to form an output signal;
• and
• a first detector configured to detect the output signal.

A method for analyzing a sample using spectroscopy, comprising:

• generating, by a laser, a pulsed light beam;
• splitting, by a first beamsplitter, the pulsed light beam into two light paths;
• phase modulating the pulsed light beam in each of the two light paths, such that the pulsed light beam in each of the two light paths is modulated at a different frequency;
• spectrally broadening the pulsed light beam in each of the two light paths, where the spectrally broadening of the pulsed light beam occurs downstream from the phase modulation;
• delaying, by a delay mechanism, the pulsed light beam in one of the two light paths, where the delaying of the pulsed light beam occurs downstream from the spectral broadening;
• recombining, by a beam combiner, the pulsed light beam from each of the two light paths to form a sample output signal;
• disposing the sample a light path downstream from the spectral broadening;
• and
• detecting, by a detector, the output signal.