About.

Our research themes are focused on some of the important problems of our times:

Realization of macroscopic quantum systems, mechanical detection of electron spin flip, development of novel nanomechanical computation architectures and nanoelectronic detection of cancer biomarkers.

 

We use cutting-edge techniques to create three-dimensional suspended mechanical structures on sub-micron and nanometer scale. These nanomechanical devices with appropriate measurement techniques enable detection of forces and torques with unprecedented sensitivity. Typical forces of interest are fundamental quantum forces or biological forces arising due to the binding of an antibody-antigen pair. Recently, we have been able to detect torque generated by electron spin flip at a level smaller than the torque created by the unwinding of a doubly-stranded DNA.

We perform every aspect of the experimental work: design and simulation, nanofabrication, materials processing, characterization, and measurements at high frequencies (< 40 GHz), short time scales (> 40 ps), high fields (< 16 tesla) and low temperatures (> 6 mK). Check out the links to get a glimpse of what we are working on now.

Nanoelectronic devices—-ultra small electronic structures, even smaller than one of the 1 billion devices in the current Intel microprocesser chip, because of their small size and large surface-to-volume ratio, enable innovative measurements of the surface charge profile of the nanowire conduction channel. Using these nano-channel devices, we have been able to detect hydrogen ions (pH), glucose, protein and—-more importantly, cancer-specific biomarkers at a level relevant for clinical use. We continue to build more sophisticated nanowire field effect transistors with complex circuits, designed to take advantage of much more advanced on-chip signal processing.


Selected Publications.

  • Micromechanical Resonator Driven by Radiation Pressure Force.

    Scientific Reports 7, 16056 (2017) https://www.nature.com/articles/s41598-017-16063-4.epdf

  • Micromechanical resonator with dielectric nonlinearity. Microsystems & Nanoengineering 4, 14 (2018) https://www.nature.com/articles/s41378-018-0013-6

  • Autoassociative Memory and Pattern Recognition in Micromechanical Oscillator Network.

    Scientific Reports 7, 411 (2017)

    http://www.nature.com/articles/s41598-017-00442-y.epdf

  • Wireless actuation of micromechanical resonators.

    Microsystems and Nanoengineering 2, 16036 (2016)

    https://www.nature.com/articles/micronano201636.pdf

  • Synchronized Oscillation in Coupled Nanomechanical Oscillators

    Science 316, 5821 (2007)

    https://science.sciencemag.org/content/316/5821/95.abstract

  • Coherent signal amplification in bistable nanomechanical oscillators by stochastic resonance.

    Nature 437, 995 (2005)

    https://www.nature.com/articles/nature04124

  • Nanomechanical detection of itinerant electron spin flip.

    Nature Nanotechnology 3, 720 (2008)

    https://www.nature.com/articles/nnano.2008.311

For all publications, click here