Research

Research

The research interests of the Sensors and Technology Lab lie broadly in the area of nano/microelectromechanical systems (N/MEMS), specifically in areas that reach into other disciplines, such as physics and medicine.  The current research involves fundamental limitations of N/MEMS, N/MEMS for free electron lasers, N/MEMS for scientific and medical tools, and the interface of microsystems with chemistry and biology.

Levitation for inertial sensing

We are currently working on levitated devices for future inertial sensing.  More information coming soon!

Radio frequency multiferroics

Multiferroic coupling using quasi-static mechanics is well established and has been successful in the development of devices such as magnetoelectric memory, nanoscale motors, and tunable radio frequency (RF) devices. However, the physics behind dynamic multiferroic coupling using mechanical waves has not been thoroughly investigated. Since mechanical waves travel much slower than the electromagnetic waves, taking advantage of them allows for the miniaturization of RF components up to a factor of 100,000 (for reference, that's like shrinking a football field down to the size of a flea). In collaboration with groups across several universities and countries, we conduct research on the interaction of mechanical oscillations with multiferroics and apply our findings to the design of miniature RF devices. Our main goal is to use this technology to develop small-scale high efficiency multiferroic antennas that will enable a new, and previously unreachable, generation of miniaturized wireless systems.

Design Optimization for MEMS

Design of microsystems that couple many physical realms is a complex proposition, but it is made feasibly by utilizing evolutionary algorithms.  As one example, we are optimizing resonators to minimize thermoelastic damping, which could lead to lower noise oscillators, higher resolution gyroscopes, or improved resonant sensors. Holes in the beam disrupt heat flow and change the coupling between the mechanical and thermal domains.  Complex multiphysics solvers are becoming more accurate and more practical and provide useful tools to explore novel designs.  With these new modeling capabilities, and new high performance computing capabilities, design optimization with complicated coupled physics is becoming practical. MEMS design, which historically has relied on a trial and error approach can benefit greatly from these new design optimization techniques.

Miniature free electron lasers

High brightness light sources, particularly free electron lasers, are the most powerful microscopes in the world. While they produce light pulses with an unrivaled combination of high brightness, short pulse duration, and high photon energy, they are typically 100s of m long or more and upwards of $1B USD to build. To complement these facilities, we are partnering with our colleagues in UCLA Physics and Astronomy to build a free electron laser that can fit in a university laboratory. To accomplish this, we are microfabricating miniature electromagnet arrays to focus and steer relativistic electron beams, from which high energy light is extracted.

Micro- to Millimeter Scale Magnetic Shielding

Recent advances in atom traps and atomic interferometry have led to chip scale atomic clocks making high precision timing and navigation devices more accessible. Further miniaturization is limited by stray fields from other systems introducing drift and increasing noise. Leveraging our expertise in electroplating thick, high permeability Permalloy over sharp topologies, we have demonstrated a process to produce conformal magnetic shielding around arbitrary geometries. Furthermore, shielding scales multiplicatively with successive layers, meaning laminations provide superior shielding compared to a single shield with the same total thickness. Microfabrication can therefore reduce size and weight by two orders of magnitude and amplify the shielding factor for appropriate characteristic lengths. Thus, we are also utilizing batch processing techniques to enclose miniature magnetic sources.

Miniature medical devices - Tactile Feedback in Robotic Surgery

Because of its minimally invasive techniques and precise micro-controllable movement, robotic surgical system sheds light on the new paradigm of surgery. However, despite its advantages, its usage is limited by an absence of tactile feedback. We are seeking for a way to measure compressive forces on a surgical grasper and to give this information back to surgeons with elaborate electrical circuits