Research
MEMS NEMS MICROFLUIDICS
For the student and the industry
Research in MEMS/NEMS/Microfluidics covers from fundamental research to device prototypes.
Fundamental
1. Materials
Faculty at CeNSE use a variety of materials as structural material for MEMS and NEMS devices. Besides the traditional material system such as silicon, silicon nitride, there is a special emphasis on ferro/piezoelectric and 2D material.
Saurabh’s group work on a wide variety of material systems such as silicon, silicon dioxide, silicon nitride, piezoelectric materials, transition metal oxides, metals and superconductors with the intent of studying material properties and various kinds physics using micro and nano-mechanical resonator platform.
Gayathri’s group focuses on ferro/piezoelectric material development which are used in micro and nano scale transducers for sensors, actuators, computing, biomedical, and communication applications.
2. Vibrations:
3. Nonlinear dynamics
Nanomechanical resonators are extremely useful tools for studying nonlinear dynamics. We use 2D material-based nanoresonator to study and manipulate these nonlinear effects. We have recently developed a technique that enables tuning of the coupling between different modes of the resonator.
4. Energy loss mechanisms and noise
Performance of micro and nano mechanical resonators is characterized by energy loss mechanisms that are prevalent in the resonator. Saurabh’s group studies different types of energy loss mechanisms such thermoelastic damping, Akhieser effect, clamping loss, air damping, internal fluid flow induced damping, electron-phonon based losses etc. Furthermore, they study the connection between energy dissipation and noise observed in microresonator based oscillators.
5. Modelling sensors and noise
Saurabh’s group works on modelling and design optimization of MEMS/NEMS sensors using topology optimization and shape optimization.
6. Opto-mechanics
Integration of mechanical elements with on-chip optical elements introduces additional functionalities that enable fundamental research as well as in sensing, signal processing, and communication. Akshay Naik’s group is involved in using optomechanical systems for metrology and sensing applications.
7. Fluid and interface dynamics
Interface phenomena dominates fluid behaviour at micro and nano behaviour. Prosenjit’s group studies fundamental fluid behaviour with the aim of developing microfluidic devices for various applications. Prof. Saurabh’s group works on embedding microfluidic channels in vibrating resonators with the aim of studying effects of fluid flow on frequency, energy loss and non-linear behaviour in these devices.
8. Active matter
Active matter pertains to collections of self-propelled objects representing a system far from thermodynamic equilibrium, commonly seen in living systems, such as bacterial suspensions swimming in fluidic media. Ambarish ‘s group has developed a class of magnetically powered self-propelled colloids which has allowed them to ask fundamental questions related to their collective behaviour and organization, and into the physics of non-equilibrium phenomena.
9. Quantum fluids
He4 and He3 continues to be a liquid even at zero Kelvin due to quantum fluctuations and shows superfluidity when sufficiently cooled. Ambarish’s group investigates these quantum fluids using bubbles containing single electrons. They use acousto-optic techniques to make these nanometres sized single electron bubbles grow to mm sizes, which can then be used to visualize the flow of superfluid helium, such as the evolution of quantized vortex lines.
Technology
1. Sensing
Various sensors have been developed in CeNSE. Some examples are pressure sensors, gyroscope, etc. Silicon remains the material of choice. However various groups are developing new generation sensors based on novel 2D and bulk materials.
2. On-chip acoustics
Gayathri’s group works on integrating multiple transduction schemes to engineer the acoustic wave propagation. Her lab explores the idea of hybrid signal processor on a single chip that modulate acoustic waves over a range of frequencies (Hz-GHz). In addition to the electromechanical aspect, she works on optical waveguide integration with acoustic transducers.
3. Magnetic nanobots
Ambarish’s group uses magnetized helical nanostructures that can be driven in different fluids using small, rotating magnetic fields. These magnetic nanobots can be maneuvered in living animals for drug delivery, thus acting as “fantastic voyagers” for biomedical applications. This technology has already been commercialized by industries working on problems in dentistry and CNS (Central Nervous System) disorders. The nanobots can also be moved inside cells to address fundamental questions in intracellular biophysics, and for cargo manipulation in microfluidic devices.
4. Micro-rheology
Ambarish’s group has developed a swimming nano-rheometer. They have used magnetic nanobots to measure viscosity and elasticity locally, which are highly suitable for rheological measurements in complex, heterogenous environments, such as inside living cells and tissues.
5. Cytometry
Classification of cell populations has many clinical applications. Prosenjit’s group works on developing microfluidic platforms for sensing multiple properties of cells and cell-clusters. Extracting electrical, mechanical and morphological information of a cell population at a single cell level is of primary interest. His group also develops ML techniques for analysing the cellular population using the captured data.
6. Droplet
Droplets are ubiquitous and are used in a wide array of applications ranging from advanced printing to bioreactors. Technologies for the generation and manipulation of droplets over a wide range of sizes (picolitre to microlitre) are being developed in Prosenjit’s laboratory.
7. Body on chips
Mimicking various organs on microfluidic chip and interconnecting them is an active area of research in Prosenjit’s lab. Such systems are used in the healthcare for drug testing and personalised treatment. By replacing human models, body-on-chips platform is more accurate, efficient and humane.
8. Wafer scale packaging
Packaging of MEMS devices is one of the greatest challenges in commercialisation. Saurabh’s group works on wafer scale encapsulation and packaging of SOI-piezoelectric and microfluidic devices.
9. Quantum microsensors
Fabrication of quantum sensors require solving complex integration challenges. Various microfabrication and heterogenous integration techniques are being developed to address these challenges. Prosenjit and Akshay’s group are jointly developing ultra-small atomic clocks. Ambarish’s group coupled magnetic nanobots with quantum sensors (NV-centre containing nanodiamonds), to make a motile quantum sensor for various on-chip applications.