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A magnetic field detection system that uses a cobalt-coated microcantilever as the detector element is demonstrated. Three different microcantilever geometries are investigated. This research also demonstrates a novel microcantilever readout technique using a dual fiber optical readout. The cantilever sensors are shown to detect changes in current as small as 0.1 A and the ability to measures current up to 5 mm from the sensor. [Copyright &y& Elsevier]

We report on the application of infrared (IR) microcalorimetric spectroscopy (μ-CalSpec) to the identification and detection of trace amounts of biological species. Our approach combines principles of photothermal IR spectroscopy with ultrasensitive microcantilever (MC) thermal detectors. We have obtained photothermal IR spectra for DNA and RNA bases and for Bacillus Cereus (an anthrax simulant) in the wavelength range of 2.5–14.5 μm (4000–690 cm−1). The measurements are accomplished by absorbing biological materials directly on a MC thermal detector. The main advantage of the developed μ-CalSpec is its unprecedented sensitivity as compared to any of the previously explored IR techniques, including FTIR and photothermal FTIR methods. Our results demonstrate that <10−9 g of a biological sample is sufficient to obtain its characteristic μ-CalSpec spectrum that contains information-rich chemical (vibrational) signatures. This opens up a new opportunity to create inexpensive high-throughput analytical systems for biochemical detection. [Copyright &y& Elsevier]

Uncooled bimaterial microcantilever detectors were fabricated and used to obtain infrared (IR) images of objects at temperatures ranging from room temperature to a few hundred °C. Images were obtained using both single 50 μm×50 μm microcantilever IR detectors and arrays of microcantilever detectors. Thermal radiation from the target object was imaged onto the detector and the resulting temperature change caused microcantilever bending due to the bimaterial effect. This micromechanical bending was measured using two different non-contact optical readout techniques and IR images were obtained. A smaller size (20 μm×20 μm) microcantilever IR detector was also used to capture IR images of near room temperature objects. [Copyright &y& Elsevier]