Generalized treatment of magneto-optical transmission filters

Abstract

This work has constructed a model for the theoretical analysis of generalized magneto-optical transmission (GMOT) filters for any relative angle between the light beam and the applied magnetic field. This model was experimentally validated and shows good agreement between the theoretical predictions and the experimental spectra. In addition, the value of examining magneto-optical filters for arbitrary angle cases was demonstrated by revealing an optimized filter with an equivalent noise bandwidth of 0.56 GHz which is approximately a factor of two better than those previously reported.

Simultaneous Faraday filtering of the Mollow triplet sidebands with the Cs-D1 clock transition

“…Faraday anomalous dispersion optical filters (FADOFs) utilize the Faraday effect in order to filter near-atom-resonant light2122. An atomic vapour cell with an external magnetic field rotates the polarization of the input light to a crossed polarization output port.…”

Velocity selection in a Doppler-broadened ensemble of atoms interacting with a monochromatic laser beam

“…For thermal ensembles of alkali-metal atoms in particular, it is easy to increase the number density substantially by a modest increase in temperature (see Appendix A of (34 )). Understanding the interplay between refractive index and absorption (35 ) is crucial for certain optical phenomena, for example the off-resonant (36 ) and slow-light Faraday effect (37 ), and in designing optical components based on thermal atomic vapours, such as compact optical isolators (38 ), Faraday filters (39 -41 ), magneto-optical transmission filters (42 ), Faraday dichroic beam splitters (43 ) and electromagnetically induced polarization rotators (44 ). Recent work has highlighted the importance of the precise experimental characterization of the susceptibility of an atomic medium inside an optical cavity, accounting for both homogeneous and inhomogeneous broadening at high optical densities, for the design and operation of quantum light-matter interfaces, particularly in the context of quantum information processing (45 -47 ).…”

Optimized ultra-narrow atomic bandpass filters via magneto-optic rotation in an unconstrained geometry

“…If we increase the cell thickness to 75 mm, to directly compare with Refs. [14,38], we calculate an optimized FOM value of 2.43 GHz −1 , with a broadly similar spectral profile to that shown in Fig. 2, but with a full width at half-maximum (FWHM) of just 110 MHz.…”

“…In systems with non-axial, non-perpendicular magnetic field geometries, no general elegant analytic solutions to the wave equation exist. Therefore, it is difficult to gain an intuitive understanding of light propagation through these media and, hence, these general magneto-optic phenomena are discussed in the literature very rarely [36][37][38]. The work of Rotondaro et al [38], to the best of our knowledge, is the only other work that deals with optical filtering in this general case; while they predicted improved filter performance for the Cs D2 line, their experimental demonstration was for a non-optimized case.…”

“…Using this FOM, we can maintain reasonably large transmission while minimizing ENBW. This FOM has previously been used to find the optimal performance of atomic Faraday filters [14,15] and, in the case of an unconstrained magnetic field angle, to theoretically predict improved performance on the Cs D2 line [38]. Figure 1 shows a schematic of the optical setup and the geometry of the situation.…”