Microcavity physics and design will be reviewed. Following an overview of applications in quantum optics, communications and biosensing, recent advances in ultra-high-Q research will be presented.

Optical microcavities

There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

Handbook of Chemistry and Physics

Sensitive optical biosensors for unlabeled targets: a review.

An overview is presented of the current state-of-the-art in silicon nanophotonic ring resonators. Basic theory of ring resonators is discussed, and applied to the peculiarities of submicron silicon photonic wire waveguides: the small dimensions and tight bend radii, sensitivity to perturbations and the boundary conditions of the fabrication processes. Theory is compared to quantitative measurements. Finally, several of the more promising applications of silicon ring resonators are discussed: filters and optical delay lines, label-free biosensors, and active rings for efficient modulators and even light sources.

/pdf/silicon-microring-resonators-3fzr4lpxbh.pdf

Silicon microring resonators

The diffraction tomography theorem is adapted to one-dimensional length measurement. The resulting spectral interferometry technique is described and the first length measurements using this technique on a model eye and on a human eye in vivo are presented.

Measurement of intraocular distances by backscattering spectral interferometry

A novel integrated optical sensor based on a cylindrical microcavity (MC) is proposed. A MC sustains so-called whispering-gallery modes (WGMs), in which the energy of the optical field can be efficiently stored. By monitoring the scattering intensity from the MC, one can detect minute changes in the refractive index of the WGM, for instance, as a result of analyte adsorption. Measurement of a change in refractive index of as little as 1024 is demonstrated experimentally. The MC-based integrated optical sensor may have a size of approximately 8 mm, and it is rugged and inexpensive.

https://www.uta.edu/rfmems/Teralum_old/vahala/118.pdf

Sensor based on an integrated optical microcavity

Planar optical waveguiding structures for application in communication networks are highly demanding with respect to low insertion loss, efficient fiber-to-chip coupling, polarization independent operation, high integration density, reliable fabrication, and last but not least cost efficiency. When applying silicon oxynitride, which is a very versatile material, planar waveguiding structures can be designed having the potential of meeting all those requirements. In this paper, we will describe the design of such a waveguiding structure, demonstrate the practical feasibility of realizing this structure and discuss the preliminary measurement results.

Design, tolerance analysis, and fabrication of silicon oxynitride based planar optical waveguides for communication devices

In this review we present an overview of the progress made in recent years in the field of integrated silicon-on-insulator (SOI) waveguide photonics with a strong emphasis on third-order nonlinear optical processes. Although the focus is on simple waveguide structures the utilization of complex structures such as microring resonators and photonic crystal structures is briefly discussed as well. Several fabrication methods are explained and methods which improve optical loss, coupling efficiency and polarization dependence are presented. As the demand for bandwidth increases communication systems are forced to use higher bit rates to accommodate the load. A consequence of high-bit-rate systems is that they require short pulses where the importance of waveguide dispersion tailoring becomes increasingly important. The impact of short pulses on the efficiency of all-optical processes is discussed and recent accomplishments in this field are presented. Numerical results of femtosecond, picosecond and nanosecond pulse propagation in SOI waveguides are compared to provide an insight into the physical processes that dominate at these different time scales. In this work we focus on two-photon absorption (TPA), free-carrier absorption (FCA), plasma dispersion and the optical Kerr effect. After describing these nonlinear effects, some other important all-optical processes based on plasma dispersion and the Kerr effect are described, namely cross-absorption modulation (XAM), self-phase modulation (SPM), cross-phase modulation (XPM), four-wave mixing (FWM) and stimulated Raman scattering (SRS). The latter provides the best hope for practical and/or commercial applications and finds its use in amplification and lasing. Furthermore, we present some guidelines for efficient numerical modelling of propagation in SOI waveguides. This review is a good starting point for those who are new in this hot and rapidly emerging field and gives an overview of important considerations that need to be taken into account when designing, fabricating and characterizing SOI waveguides for ultrafast third-order nonlinear all-optical processing.

https://iopscience.iop.org/article/10.1088/0022-3727/40/14/R01/pdf

Ultrafast nonlinear all-optical processes in silicon-on-insulator waveguides

Using data available from literature for hydrogen in the liquid and solid phases the authors constructed a consistent equation of state valid over a large part of the operating range of the diamond anvil cell. A large part of the experimental data is reproduced within 0.1% and practically all data within 0.5%. From this equation of state they derived the thermodynamic properties of molecular hydrogen. The volume, entropy, Gibbs free energy and enthalpy are tabulated as a function of temperature and pressure for P<or=1 Mbar and 100K<or=T<or=1000K.

https://iopscience.iop.org/article/10.1088/0022-3719/19/19/013/pdf

Thermodynamic properties of hydrogen at pressures up to 1 Mbar and temperatures between 100 and 1000K

The refractive index of silicon oxynitride (SiON), a widely used material for integrated optics devices, can be chosen in a wide range between 1.45-2.0. We describe how the consequent large design freedom can be exploited on the one hand for a "standard" polarization independent optical channel waveguide having a favorable tradeoff between efficient fiberchip coupling and small bend radii (compact devices) and on the other hand for special-purpose and hybrid components where the refractive index should be finely adjusted for obtaining the desired functionality. We illustrate the applicability of SiON by describing a few devices for optical filtering in a new architecture for wavelength multiplexing, modulation, polarization splitting and second-harmonic generation.

Alfred Driessen

Papers

Sensor based on an integrated optical microcavity

Design, tolerance analysis, and fabrication of silicon oxynitride based planar optical waveguides for communication devices

Ultrafast nonlinear all-optical processes in silicon-on-insulator waveguides

Thermodynamic properties of hydrogen at pressures up to 1 Mbar and temperatures between 100 and 1000K

Silicon oxynitride planar waveguiding structures for application in optical communication