Fatima of Princeton

It's a Small, Small World



When Fatima Toor '04 of Lahore, Pakistan, joined the first class of Picker engineering students at Smith College , she brought to the table a keen appreciation of math and applied sciences; what she did not bring was confidence in her ability to talk about them in public. She's different now. In the past four years, she has stood before large gatherings of engineering and physics students as well as industry managers and professional engineers and discussed her own undergraduate research, including a presentation on process optimization for negative photoresists. "I've changed dramatically," notes Toor, who received a Jean Picker Fellowship for her engineering studies at Smith.





With a double major in physics and engineering, Toor is drawn to the emerging field of nanoelectronics, a combination of nuclear quantum physics and electronics on a nanometer scale. With countless possible applications including miniature computers or tiny switches for optical networks, nanoelectronics seems to be a natural for someone who counts among her favorite films the 1980s Back to the Future sci-fi trilogy, with its dramatic and colorfully imagined technologies capable of moving humans through time and space.




After a summer internship where she conducted research in electronics optical packaging (for which she won an IBM award) in the microelectronics lab at IBM's Thomas J. Watson Research Center in Yorktown, New York, she says, "I realized how exciting the [nanoelectronics] field is." She returns to the same IBM division this summer to continue the work and then goes on this fall to start her doctoral work in electrical engineering; she has been accepted at Princeton's School of Engineering and Applied Science and is waiting word from four other schools.





"My dream," Toor says, "is to connect research in nanoelectronics with innovations that will make a big difference to society -- like the way the Internet revolutionized communications in our culture. I hope my work in nanoelectronics will accomplish something similar some day."










Abstract Submitted
for the MAR09 Meeting of
The American Physical Society

Temporal Wavelength Multiplexing of a Quantum Cascade Laser

FATIMA TOOR, AMIRALI SHANECHI, JIANXIN
CHEN, CLAIRE GMACHL, Electrical Engineering, Princeton Univer-
sity —



Quantum cascade (QC) laser based sensor systems in the mid-
infrared wavelength range (3-30 µm) have applications in environmental,
industrial and medical trace gas sensing. QC laser- based spectroscopic
techniques have been developed by several research groups. However,
more research work is needed to make these techniques more compact
and field deployable. One approach to compactness is to have spectral
versatility from a single device. Here we report work on a QC laser
based system that is both temporally and wavelength multiplexed, that
is, it can emit two different wavelengths at two alternate time slots. A
bi-directional and multi-wavelength QC laser source that emits at 10.2
µm wavelength for positive polarity current and 8.6 µm for negative
polarity current is used. A system is designed so that a single pulsed
current source is the input to a pulse-alternator circuit that flips the
polarity of every other pulse. The output of the circuit is connected
to the bi-directional and multi-wavelength QC laser to emit two differ-
ent wavelengths for alternate pulses. Contributions by Gary Shu at the
beginning of the work are acknowledged.
1
This work is supported in part by MIRTHE (NSF-ERC).




Fatima Toor

Electrical Engineering, Princeton University
Date submitted: 20 Nov 2008