Third year Physics graduate student Steven Buczkowski has been selected to receive a NASA Earth and Space Sciences Fellowship. Steven's proposal entitled "Rainbow and Cloud Side Remote Sensing: A Novel Look at Cloud-Aerosol Interaction and Its Effect on Cloud Evolution" was one of 50 proposals accepted, out of 200 received.

A member of the UMBC Atmospheric Physics PhD program, Steven will work with his advisor, Dr. Vanderlei Martins, to characterize and develop retrieval algorithms for a novel suite of visible and infra-red cameras developed by Dr. Martins and his collaborators here and at NASA Goddard Space Flight Center.

Clouds on Earth require some airborne aerosol in order to form but regional enhancements in aerosol load (e.g. from biomass burning, etc) can have a profound effect on their evolution. These effects can range from shifting precipitation patterns to changes in planetary albedo which could influence global climate. Steven's work with Dr. Martins will seek to better understand the influence of aerosol amount and type on cloud development.

In former times, materials were developed tuning their chemical composition to get the desired properties. Hence, material analysis was used to get the chemical composition in a broad sense. Though initially based on wet-chemistry processes, material analysis by physical methods turned into an ever-growing field. Ion Beam Analysis and Inductively Coupled Plasma Mass Spectrometry are just two examples of a field in which the detection limits, and sample sizes are being extraordinarily reduced enabling nowadays the measurement of sub-ppb levels of any element of the whole periodic table in microscopic samples. The billionaire semiconductor industry is just one of the applications of modern ultra low detection analysis by physical (dry) methods. Trace elements in materials can be used to trace archaeological technologies. Trace elements in blood serum may be used in the future to trace diseases, eventually cancer. Trace elements in aerosols can indicate its origins and transport properties. In this new era, the question whether an element is or is not present in a sample has changed to what are the elemental concentration levels and how they correlate to the bio-physical-chemical processes involved.

Location: Physics Bldg., Room 401
Coffee: 3:15 p.m.

Congratulations go to Physics graduate students Steven Buczkowski and Kimberly Wall for winning the 2007-08 Outstanding Graduate Teaching Assistant of the Year Award! This award acknowledges and recognizes outstanding graduate teaching assistants for their contributions to the teaching mission of the Physics department at UMBC.

Steve and Kim were presented with a plaque and a check for $500 at the Physics Colloquium on September 3, 2008.

Anyone who travels has likely heard the following warning: “FAA regulations prohibit the use of portable electronic devices during takeoff or landing.” The modern aircraft contains an ever-growing array of electronic sensors used in navigation and communication. At the same, time, we have seen a rapid explosion not only in the number of handheld electronic appliances carried by passengers, but also in their frequencies of operation. This has lead to growing concern that electromagnetic radiation from such devices could interfere with navigation and communication.

One potential solution to this problem is to replace the coaxial cables and wires normally used to transmit electronic signals in the aircraft with optical fibers. Compared to coaxial cables, optical fibers are smaller, lighter, and less expensive. The bandwidth available in a single fiber is large enough to accommodate the data from thousands of coaxial cables, and the loss in optical fiber is negligible in comparison to coaxial cables, especially at microwave frequencies. Most importantly, optical fibers are completely immune to electromagnetic interference, which makes them especially attractive for avionic sensor networks. The key challenge is to find a ways to modulate and demodulate analog microwave signals onto an optical carrier without distorting or impairing the microwave signal.

In this talk, I will discuss our recent research on using phase modulation instead of more commonly-used intensity modulation to impose a microwave signal on an optical carrier. To date, there has been very little research on developing low-distortion linearized phase-modulation systems. Unlike earlier intensity-modulation schemes, which often required multiple interconnected modulators or signal pre-distortion, our system is unique in that it uses only a single electrooptic phase modulator driven by an unmodified input signal, and could entirely eliminate the third-order intermodulation distortion that usually limits the dynamic range.

Location: Physics Bldg., Room 401
Coffee: 3:15 p.m.

The extragalactic background light (EBL) that permeates the Universe in the optical-IR is essentially an integral of the light produced from the time the first stars were formed in our Universe until now. As such, it is a quantity that is very closely connected to the galaxy/ large scale structure formation in our Universe. Unfortunately, measuring the EBL has been proven practically impossible, for very simple reasons that I will discuss in the first part of my talk. Luckily, we found an unexpected, parameter-free way to break the deadlock of measuring the EBL with GLAST, NASA's new gamma-ray satellite. This will be the second part of my talk. GLAST measurements are underway and the determination will take about two years.

Location: Physics Bldg., Room 401
Coffee: 3:15 p.m.

Many new device applications in micro- and nanotechnology require the ability to fabricate complex, 3D structures. Conventional lithographic techniques are not well suited to the creation of many such structures, which has fueled interest in the development of novel fabrication techniques. One rapidly emerging technology for 3D fabrication is multiphoton absorption polymerization (MAP). In MAP, a tightly focused laser beam is used to exposure a photoresist exclusively at the laser focal point. By moving this focal point over a desired pattern in three dimensions, arbitrarily complex structures with feature sizes as small as 100 nm can be created. I will discuss some of our recent progress in expanding the capabilities of MAP as well as in creating functional devices.

Location: Physics Bldg., Room 401
Coffee: 3:15 p.m.