Our group, formerly known
as the Photonics Laboratory, was started in 1997 by Dr. Wang and his several
graduate students from scratch. It has since experienced substantial growth.
Currently, CPT's research ranges from basic science for answering fundamental
questions in contemporary physics to engineering innovations for solving
real-world problems. Its work can be divided into three areas, including
harsh environment sensors, narrow linewidth laser characterization and
test of physical constant's constancy.
News
Headlines
Test
on the Constancy of Speed of Light CPT researchers lately
completed the first phase of an experiment to test on the constancy of
speed of light. The speed of light in vacuum is one of the most fundamental
constants and its value has been assumed to be constant. Our experiment
is to find if this value depends on light history or photon age. Based
on an active 50km Mach-Zehnder fiber optic interferometer, the speeds
of light from the Sun and local light sources are differentially measured
and compared. The result indicates that this value does not vary at the
level of 1.6 x10 -11 per year of light
travel. To our best knowledge, this is the first measurement of this kind
to experimentally prove the constancy of speed of light.
Nanofilm Enabled Optical Sensors
for Label-free DNA Detection Traditionally,
DNA samples are labeled with a fluorescence indicator for sequence identification.
But labeled samples cost 20 times more than un-labeled samples. For sake
of cost saving, it is thus desirable to develop sensors that allow rapid
and reliable detection of un-labeled DNA samples. A novel optical sensor
was recently demonstrated at CPT for label-free DNA sequence detection.
The test results show the new sensor can detect DNA quantities as small
as 1.7ng with contact times of about 5 minutes.
Ultra-high
Speed Optical Spectrometer
Optical spectrum measurement is highly desirable
in a wide range of applications. Current spectrometers are mostly coupled-charge-device
(CCD) or Fourier-transform spectrometers (FTS) based. However, the charge
accumulation and the mechanical scanning that are necessary in the CCD and
FTS operations limit their applications to only low speed measurement. CPT
researchers recently demonstrated a new spectrum measurement technology
based on conversion of optical spectrum into a time domain signal. This
new method can potentially increase the speed to a megahertz level, which
would represent a speed increase by at least four orders of magnitude.
CPT Students
Honored
Five CPT students were recently recognized
with various awards as below: Paul Torgersen Award: Yizheng Zhu,
Xingwei Wang, and Navin J. Manjooran received this award with the first,
second and third places, respectively. Only three Ph.D. students in the
College of Engineering are selected each yearfor this honor, and this
year all the three are from CPT! Outstanding Oversea Graduate Student:
Yizheng Zhu received this $5,000 award by the Education Ministry of China.
Only about 50 among all the Chinese students in the U.S. were chosen to
receive this award this year. Bradley Fellow: Evan Lally,
current CPT M. S. student, received the Bradley Fellowship ($25,000 plus
full tuition each year for three years) to support his Ph.D. study at
Virginia Tech. ONR Yong Investigator Award: Former
CPT student, Dr. Hai Xiao, now a professor at New Mexico Tech, received
this honor. Only seven (used to be twenty eight in the past) were awarded
this year nationwide.
For more current CPT news, see the
Announcements page
