Heavy metals are a major public health concern and their on-site detection in water supplies is not well served by existing lab techniques. We develop a new multi-modal platform comprising functionalized quantum dots of two-dimensional materials (2D-QDs) for the sensing of four highly-toxic heavy metal pollutants (arsenic, cadmium, lead and mercury). The zero-dimensional nature of quantum dots brings essential properties necessary for fluorescence-based chemical sensing of heavy metals in the field. We focus on one type of 2D material, molybdenum disulfide (MoS2), which is a direct band gap semiconductor when produced as a monolayer. To fabricate and functionalize the 2D-QDs, we expose flakes of MoS2 suspended in a solution to a pulsed laser. This technique allows us to simultaneously functionalize the 2D-QDs, so that they become sensitive to a specific pollutant metal, and control their fluorescence wavelength, so that 2D-QDs functionalized for different target metals will produce distinguishable optical signals. By combining multiple types of functionalized 2D-QDs into a single solution capable of simultaneously identifying various heavy metals, we expect to advance a range of applications that require a field-deployable solution. These include for example, rapid contaminant point source identification, and water analysis of heavy metals in developing countries where conventional equipment is too costly.
Two-Dimensional Quantum Materials and Heterostructures
Two-dimensional (2D) layers just one atom thick can be stripped from certain materials, such as graphene.
June 1, 2017
Novel Infrared Camera Based on Quantum Sensors for Biomedical Applications
Summary In this project we develop a novel infrared camera with low noise and high detection efficiency for biomedical applications of optical coherence tomography (OCT) using quantum materials. OCT is a technique used to image the back of the eye and allow for the diagnosis of detrimental eye conditions, for e.g., macular degeneration, diabetic retinopathy […]
March 13, 2019
Entangled Photon Orbital Angular Momentum Arrays
Summary Arrays of orbital angular momentum (OAM) states of light are a new form of structured light so far relatively unexplored in quantum information science. Unlike spin angular momentum of light, which is related to light’s polarization and covers two dimensions, OAM states, sometimes described as ‘donut beams’ due to the shape of the field […]
September 19, 2019
A Reformulation of Quantum Game Theory
Summary Classical game theory – conducted at the interface between economics and computer science – has found applications in topics ranging from networking and security to online markets. Despite over 20 years of research into connections between game theory and quantum information, we have yet to see any significant implications of quantum information when applied […]
April 1, 2020