We have studied photoluminescence (PL) properties of vacuum pump mineral oil as a function the type and intensity ionizing radiation exposure. The has simple aliphatic structure, which possesses no chromophore in traditional sense. Unexpected PL characteristic features such variation emission peak wavelength depending on excitation dramatically increasing with dose. observed behavior can be und...

We present a density-matrix-based transport model applicable to quantum cascade lasers which computes both linear and nonlinear optical properties coherently and nonperturbatively. The model is applied to a dual-active-region midinfrared quantum cascade laser which generates terahertz radiation at the difference frequency between two midinfrared pumps. A new mechanism for terahertz generation i...

Objectives: In this article, a new procedure for increasing the light penetration depth in a tissue is studied and simulated. It has been reported that the most important problem in biomedical optical imaging relates to the light penetration depth, and so this makes a dramatic restriction on its applications. In the optical imaging method, the detection of the backscattered pho...

In this paper, we will review both past and recent progresses in the generation, detection and application of intense terahertz (THz) radiation. We will restrict the review to laser based intense few-cycle THz sources, and thus will not include sources such as synchrotron-based or narrowband sources. We will first review the various methods used for generating intense THz radiation, including p...

background: various variance reduction techniques such as forced detection (fd) have been implemented in monte carlo (mc) simulation of nuclear medicine in an effort to decrease the simulation time while keeping accuracy. however most of these techniques still result in very long mc simulation times for being implemented into routine use. materials and methods: convolution-based forced detectio...

The generation and detection of terahertz ~THz! radiation using ultrashort optical pulses has been intensively studied during the last decade. The pulse width of commercially available mode-locked Ti:sapphire lasers is approaching 10 fs. With such ultrashort pulses, a wider detection bandwidth is expected to be possible. Coherent detection of THz radiation based on a photoconductive ~PC! antenn...

Evanescent radiation-molecule interactions in an optical microcavity device are characterized. The device is operated at whispering-gallery modes, and consists of a microcavity and a micro-waveguide coupled by a sub-micrometer air-gap. Under optical resonance, a strong evanescent field arises along the periphery of the circular resonating microcavity. This radiation will certainly interact with...

The concept of optical antennas in physical optics is still evolving. Like the antennas used in the radio frequency (RF) regime, the aspiration of optical antennas is to localize the free propagating radiation energy, and vice versa. For this purpose, optical antennas utilize the distinctive properties of metal nanostructures, which are strong plasmonic coupling elements at the optical regime. ...

Breast cancer is one of the most common cancers among the population of the Western world. Diagnostic methods include mammography, ultrasound, and magnetic resonance; meanwhile, nuclear medicine techniques have a secondary role, being useful in regional assessment and therapy followup. Optical imaging is a very promising imaging technique that uses near-infrared light to assess optical properti...