Nanoresonator Enhancement of Majorana-Fermion-Induced Slow Light in Superconducting Iron Chains

We theoretically investigate Fano resonance in the absorption spectrum of a quantum dot (QD) based on a hybrid QD-nanomechanical resonator (QD–NR) system mediated by Majorana fermions (MFs) in superconducting iron (Fe) chains. The absorption spectra exhibit a series of asymmetric Fano line shapes, which are accompanied by the rapid normal phase dispersion and induce the optical propagation properties such as the slow light effect under suitable parametric regimes. The results indicated that the slow light induced by MFs can be obtained under different coupling regimes and different detuning regimes. Moreover, we also investigated the role of the NR, and the NR behaving as a phonon cavity enhances the slow light effect.

Measuring the Effects of Temperature on Optical Propagation in Heated Tissues Using Point Radiance Spectroscopy

Laser interstitial thermal therapy (LITT) is a minimally invasive therapy in which light is delivered using optical fibers inserted into tissue to treat malignant tumours. Heating tissue above 55°C causes tissue coagulation, creating non-viable tissue. Previous work has demonstrated that radiance measurements are sensitive to heat-induced changes in tissue optical properties. This study investigates the use of radiance measurements to differentiate permanent temperature-induced changes in optical propagation, which reflect thermal damage, from any transient changes in optical propagation. Experiments in water using our white-light point radiance spectroscopy (PRS) technique demonstrate that PRS is sensitive to detect optical absorption and temperature-dependence in the optical absorption of water, and a change in the acceptance cone with temperature. Experimental results using PRS in heated ex vivo porcine tissue show that the optical signal mainly represents permanent thermal damage and only a small part of the signal represent a temperature-dependent change due to water.

Measuring the Effects of Temperature on Optical Propagation in Heated Tissues Using Point Radiance Spectroscopy

Laser interstitial thermal therapy (LITT) is a minimally invasive therapy in which light is delivered using optical fibers inserted into tissue to treat malignant tumours. Heating tissue above 55°C causes tissue coagulation, creating non-viable tissue. Previous work has demonstrated that radiance measurements are sensitive to heat-induced changes in tissue optical properties. This study investigates the use of radiance measurements to differentiate permanent temperature-induced changes in optical propagation, which reflect thermal damage, from any transient changes in optical propagation. Experiments in water using our white-light point radiance spectroscopy (PRS) technique demonstrate that PRS is sensitive to detect optical absorption and temperature-dependence in the optical absorption of water, and a change in the acceptance cone with temperature. Experimental results using PRS in heated ex vivo porcine tissue show that the optical signal mainly represents permanent thermal damage and only a small part of the signal represent a temperature-dependent change due to water.

Optical Nanocomposites Containing Low Refractive Index MgF2 Nanoparticles

Nanoparticles composed of magnesium fluoride were successfully introduced into polymer matrices used for the fabrication of planar optical waveguides. Optical layers without visible scattering were successfully prepared. The transparent nanocomposites were formulated by direct mixing of modified MgF2 nanoparticles with fluorinated co-polymer matrix or acrylate monomer mixture with a help of additional solvent. An addition of MgF2 nanoparticles results in decrease of refractive index and thermo-optic coefficient of the polymer but increases substantially the optical propagation losses for planar waveguide at 1547 nm.