Microwave Modulation of Light in Paramagnetic Crystals

Abstract

halides increases strongly upon decrease of the ratio S/D (where S is the space between adjacent halogen ions in a [110] direction of the normal lattice and D the diameter of the halogen atom). In going from KBr to NaBr, S/D diminishes by a factor of approximately two, while the energy needed to form an F center becomes 600 times greater. In the cesium halides, as one goes from CsCl to Csl, the corresponding S/D ratio decreases by a factor of 2.5. Consequently, one might

Probing the electronic structure of transition metal ion centres in proteins by coherent Raman-detected electron paramagnetic resonance spectroscopy

“…While the description of the experiment in terms of coherent Raman scattering has been used successfully, an alternative picture derived from MCD spectroscopy is sometimes more useful: the transverse magnetization induces a circular dichroism for light propagating through the sample in a direction perpendicular to the static magnetic field [6,14]. For a given circular polarization, the Larmor precession modulates the sample absorbance at the microwave frequency.…”

“…This model is quantitatively valid as long as the optical linewidth is large compared to the microwave frequency and provided that optical hole-burning effects are absent. In this case we may continue to use the concept of an optical transition probability on a timescale short compared to the microwave period [14]. This in turn allows us to describe the experiment using the well-established theories of conventional EPR [15] and magneto-optics [16].…”

Optically detected electron paramagnetic resonance by microwave modulated magnetic circular dichroism

“…The concept of a microwave modulated MCD is valid as long as the linewidth of the optical transition is much broader than the microwave frequency. 15 This means that the concept of an optical transition probability is valid on a time scale much shorter than the Larmor period.…”

“…13 As an alternative to the coherent Raman picture, this experiment can also be considered as a measurement of an oscillating circular dichroism induced by the precessing transverse magnetization of the electron spin. [14][15][16] A circularly polarized light beam is thus amplitude modulated at the microwave frequency. It is the purpose of this paper to discuss the implications of this model and to assess its validity by comparing experimental results from two prototypical systems; a frozen, aqueous solution of the metalloprotein cytochrome c-551, and a single crystal of ruby (Cr 3ϩ :Al 2 O 3 ).…”

Towards a millivolt optical modulator with nano-slot waveguides

“…Optical modulators are fundamental components of optical data transmission systems, serving as the gateway from the electrical to the optical domain [1]. High-bandwidth optical signals can be transmitted through optical fibers with low loss and low latency [2] making optical data transmission an attractive option for many applications.…”