Shubhra Gangopadhyay

Learn More
Near-infrared epsilon-near-zero (ENZ) metamaterial slabs based on silver-germanium (Ag-Ge) multilayers are experimentally demonstrated. Transmission, reflection and absorption spectra are characterized and used to determine the complex refractive indices and the effective permittivities of the ENZ metamaterial slabs, which match the results obtained from(More)
  • Tim Dallas, Mark Holtz, Jordan M Berg, Shubhra Gangopadhyay, Mark W Holtz, Shubhra M Gangopadhyay
  • 2002
 We describe a three-course introductory sequence in fluorescence-based microanalytical systems. The series is aimed at beginning graduate students and advanced undergraduates who have an interest in MEMS and microelectronics. The first course is introductory with the objective of educating students in the basics of silicon microfabrication. Devices are(More)
Here we describe a method to fabricate a multi-channel high-throughput microchip device for measurement of quantal transmitter release from individual cells. Instead of bringing carbon-fiber electrodes to cells, the device uses a surface chemistry approach to bring cells to an array of electrochemical microelectrodes. The microelectrodes are small and(More)
Photorelease of caged Ca(2+) is a uniquely powerful tool to study the dynamics of Ca(2+)-triggered exocytosis from individual cells. Using photolithography and other microfabrication techniques, we have developed transparent microchip devices to enable photorelease of caged Ca(2+), together with electrochemical detection of quantal catecholamine secretion(More)
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract We introduce nanogap-embedded silver plasmonic gratings for single-molecule (SM) visualization using an epifluorescence microscope. This silver plasmonic plat‐ form was fabricated by a cost-effective nano-imprint lithography(More)
We report metal/p-Si contact barrier modification through the introduction of either "isolated" or "nonisolated" tilted-target-sputtered sub-2 nm platinum nanoparticles (Pt NPs) in combination with either a 0.98 nm Atomic Layer Deposited Al2O3 or a 1.6 nm chemically grown SiO2 dielectric layer, or both. Here, we study the role of these Pt NP's size(More)
The optical nonlocality in metal-dielectric multilayer metamaterials is characterized experimentally as a function of the angle of incidence with respect to the TE-polarized incident light. The physical mechanism of the difference between the nonlocal effective permittivity and the effective-medium-theory-based effective permittivity depending on the(More)
The optical nonlocality in metal-dielectric multilayer meta-materials is characterized experimentally as a function of the angle of incidence with respect to the TE-polarized incident light. The physical mechanism of the difference between the nonlocal effective permittivity and the effective-medium-theory-based effective permittivity depending on the(More)
BACKGROUND Biofilms occur on a wide variety of surfaces including metals, ceramics, glass etc. and often leads to accumulation of large number of various microorganisms on the surfaces. This biofilm growth is highly undesirable in most cases as biofilms can cause degradation of the instruments and its performance along with contamination of the samples(More)