Engineering topics

Dowran, Mohammadjavad

Publications and source records attributed to Dowran, Mohammadjavad.

4 records

DOE OSTI2024

Parallel Quantum-Enhanced Sensing

Quantum metrology takes advantage of quantum correlations to enhance the sensitivity of sensors and measurement techniques beyond their fundamental classical limit, given by the shot-noise limit. The use of both temporal and spatial correlations present in quantum states of light can extend quantum-enhanced sensing to a parallel configuration that can simultaneously probe an array of sensors or independently measure multiple parameters. To this end, we use multispatial-mode bright twin beams of light, which are characterized by independent quantum-correlated spatial subregions in addition to quantum temporal correlations, to probe a four-sensor quadrant plasmonic array. We show that it is possible to independently and simultaneously measure local changes in refractive index for all four sensors with a quantum enhancement in sensitivity in the range of 22% to 24% over the corresponding classical configuration. Finally, these results provide a first step toward highly parallel spatially resolved quantum-enhanced sensing techniques and pave the way toward more complex quantum sensing and quantum imaging platforms.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2022

Lattice Resonances of Nanohole Arrays for Quantum Enhanced Sensing

We report periodic arrays of nanoholes perforated in metallic thin films interact strongly with light and produce large electromagnetic near-field enhancements in their vicinity. As a result, the optical response of these systems is very sensitive to changes in their dielectric environment, thus making them an exceptional platform for the development of compact optical sensors. Given that these systems already operate at the shot-noise limit when used as optical sensors, their sensing capabilities can be enhanced beyond this limit by probing them with quantum light, such as squeezed or entangled states. Motivated by this goal, here, we present a comparative theoretical analysis of the quantum enhanced sensing capabilities of metallic nanohole arrays with one and two holes per unit cell. Through a detailed investigation of their optical response, we find that the two-hole array supports resonances that are narrower and stronger than its one-hole counterpart, and therefore have a higher fundamental sensitivity limit as defined by the quantum Cramer-Rao bound. We validate the optical response of the analyzed arrays with experimental measurements of the reflectance of representative samples. The results of this work advance our understanding of the optical response of these systems and pave the way for developing sensing platforms capable of taking full advantage of the resources offered by quantum states of light.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2018

Quantum Plasmonic Sensing Beyond the Classical Limit

The ultimate sensitivity of any optically based measurement using classical resources (for example, laser or thermal light) is constrained by the photon shot noise limit (SNL). However, quantum states of light, in which photon pairs have quantum correlations or entanglement, off er a path beyond this limit. In particular, “squeezing” in these quantum states makes it possible to lower the noise in the detection system below the SNL. This can signifi cantly enhance the sensitivity of real-world devices and could thus revolutionize optical-based sensing applications

47 OTHER INSTRUMENTATION↗

DOE OSTI2018

Quantum-enhanced plasmonic sensing

Quantum resources can enhance the sensitivity of a device beyond the classical shot noise limit and, as a result, revolutionize the field of metrology through the development of quantum-enhanced sensors. In particular, plasmonic sensors, which are widely used in biological and chemical sensing applications, offer a unique opportunity to bring such an enhancement to real-life devices. Here, we use bright entangled twin beams to enhance the sensitivity of a plasmonic sensor used to measure local changes in the refractive index. We demonstrate a 56% quantum enhancement in the sensitivity of a state-of-the-art plasmonic sensor when compared with the corresponding classical configuration and a 24% quantum enhancement when compared to an optimal single-beam classical configuration. We measure sensitivities on the order of 10 –10 RIU / √Hz, nearly 5 orders of magnitude better than previous proof-of-principle implementations of quantum-enhanced plasmonic sensors. Furthermore, these results promise significant enhancements in ultratrace label-free plasmonic sensing and will find their way into areas ranging from biomedical applications to chemical detection.

47 OTHER INSTRUMENTATION↗