Advantages of maximum likelihood methods for PRBS modulated TOF electron spectrometry

We consider the recovery of spectra from pseudo-random binary sequence (PRBS) modulated TOF-HREELS data. The effects of the Poisson noise distribution and the non-ideal behavior of an “interleaved comb” chopper are simulated. We show, for the first time, that maximum likelihood methods can be combined with PRBS modulation to achieve resolution enhancement, while properly accounting for the Poisson noise distribution and artifacts introduced by the chopper. Our results indicate that meV resolution, similar to that of modern high resolution electron spectrometers, can be achieved with a dramatic performance advantage over conventional, serial detection analyzers.