Events
June 17 |
The 11th Annual Future of Light Symposium: Biophotonics Tuesday, June 17th, 2008 * There is no charge for the conference unless, you register and do not attend. After the conference your credit card will be charged a nominal $100. If you provide information one week prior to the conference that you will be unable to attend, your credit card will not be charged. |
| March 24 | Photonics Forum Colloquium Room, 9th Floor Dr. Theodore D. Moustakas The GaN R&D effort at Boston University addresses both fundamental issues as well as device applications. The fundamental issues include the epitaxial growth of the entire family of III-Nitride Semiconductors, the development of probes for monitoring the growth in-situ, the study of the crystal structure, the theoretical and experimental investigation of the electronic structure and defects. The device applications include emitters and detectors in the UV, LEDs and lasers in the visible, as well as infrared and terahertz emitters based on intersubband transitions in AlGaN Multiple Quantum Wells (MQWs) In this talk I will briefly review the various activities of the program and focus particularly on our research related to LEDs for solid state lighting and various applications in the UV. Such devices are based on InGaN or AlGaN Multiple Quantum Wells (MQWs) or Quantum Dots (QDs). The current emphasis of the program is to develop such devices using textured QWs grown on non-polar GaN templates. The physics and benefits of using textured MQWs in LED structures based on these polar materials will be addressed. This approach leads to an increase in internal quantum efficiency by suppressing the polarization degrading effects and an increase in extraction efficiency due to textured external surface. Dr. Lee E Goldstein Alzheimer’s disease (AD) is a leading contributor to mortality, morbidity, and healthcare costs. Although hundreds of emerging AD therapeutics aimed at the underlying disease show great promise, effective treatment will remain elusive unless coupled with early (pre-symptomatic) disease detection. Development of new diagnostic technology for screening and early detection is now an urgent national research priority. Based on our discovery of AD-linked beta-amyloid (Aß) pathology in the lens of the eye (Goldstein et al., Lancet, 2003), we are now developing innovative non-invasive bio-optical laser technology for quantitative molecular diagnostic detection of AD from the very earliest stages of the disease, before onset of cognitive symptoms and irreparable damage to the brain. A new paradigm linking early molecular detection with early therapeutic intervention holds near-term promise for effective treatment for this devastating disease. |
| February 25 | Photonics Forum Colloquium Room, 9th Floor Roberto Reif Tissues are typically characterized by their optical properties that are defined by scattering and absorption. The scattering depends on the morphological composition of the scattering centers (i.e. size and size distribution), while the absorption depends on the biochemical composition (i.e. blood volume fraction and oxygen saturation). Monte Carlo simulations and experiments in tissue phantoms were used to empirically develop an analytical model that characterizes the reflectance spectrum in turbid media. The model extracts the optical properties (scattering and absorption coefficients) of the medium at small source-detector separations, for which the diffusion approximation is not valid. The accuracy of the model and the inversion algorithm were investigated and validated. The model is tested in vivo on patients with Inflammatory Bowel Disease yielding a high sensitivity and specificity. Finally, the influence of probe pressures is investigated as a source of noise. Kurt Schoener The technologies used by neurophysiologists to interrogate and understand brain function, which are many, range from the microscopic to the macroscopic but lack an acceptable mesoscopic tool. The microscopic techniques, such as microelectrodes, patch-clamping, calcium dyes, and two-photon microscopy, capture subneuronal, single-neuron, or very-small-network dynamics. The macroscopic, such as MRI, PET, EEG, and MEG, capture cortex, subcortex, or small-volume dynamics. What is needed is a technology that can interrogate many thousands of neurons simultaneously, with single neuron resolution, and resolution on a time scale that can track single action potential propagation. Attempts to provide such mesoscopic devices have been made for decades, including voltage-sensitive dyes (VSD), microelectrode arrays, and intrinsic optical signals (IOS). However, none have been able to overcome their specific deficiencies in order to become useful to the researcher. This work has shown preliminary results that indicate that exploiting the field-induced changes in birefringence that occur when a neuron is activated, will lead to a device with the temporal and spatial resolution required to meet the need for a mesoscopic imaging technology for neurophysiologists. |
| January 29 | Nitride Semiconductor Optoelectronics Research at Army Research Laboratory for Defense and Security Applications Dr. Michael Wraback 9th Floor, Photonics Center The family of III-V nitride semiconductors, comprised primarily of GaN, AlN, InN, and alloys thereof, can be employed in optoelectronic devices covering the electromagnetic spectrum from THz to the ultraviolet. In this talk, defense and security applications of nitride semiconductor optoelectronic devices are addressed, with emphasis on ongoing research at the Army Research Laboratory. The role of ultraviolet LEDs and lasers in chem/bio detection and water/air/surface purification will be discussed, including the development of AlGaN containing nanoscale compositional inhomogeneities for improved internal quantum efficiency. |
| January 28 | Incubator Forum Colloguium Room, 9th Floor We invite you and your colleagues to join us at the second Incubator Forum where incubator companies on the 6th floor of the Photonics Center will introduce us to their technology, research activities, and challenges as a startup company and their experiences as a part of the Boston University community! Schedule |
