2 Projects, page 1 of 1
Processes in the microscopic world are extremely well described by quantum theory, but yet little is known about the transition to the classical world at macroscopic scales. For example, can a macroscopic object such as a virus be put into a quantum superposition, and if not, what are the processes at these length and mass scales that prevent this? These types of questions are not only important for our fundamental understanding of the world but they will also impact on the development of future engineered macroscopic quantum systems. Until very recently these questions remained a primarily theoretical pursuit because the experimental methods required to prepare and maintain the delicate quantum states in the presence of environmental noise did not exist. This is because even weak interactions between a quantum system and its environment can rapidly destroy them. As such, these systems must be prepared in well controlled isolation, and typically, this often requires cooling to very low temperatures. New experimental techniques now offer the prospect for laboratory tests of macroscopic quantum mechanics. This field, collectively known as quantum cavity optomechanics, uses the controlled interaction of light with the mechanical motion of nanoscale and microscale oscillators, to coherently control their motion. To date quantum ground state cooling has been demonstrated in only a handful of these solid-state devices but a macroscopic superposition, and even non-classical motion, has yet to be observed. A new optomechanical oscillator system that is levitated in vacuum has recently been developed by the UCL group. It uses a novel configuration of electric and optical fields to achieve extremely good isolation from the environment. Cooling from room temperatures down to milliKelvin temperatures has been achieved for the first time, by employing a technique called cavity cooling, with quantum ground state cooling now within reach. Our aim in this research programme is to build on this initial success by using the hybrid technologies to create a well controlled, low dissipation macroscopic oscillator, that can be prepared in its absolute ground state. This system will allow us to explore macroscopic quantum mechanics by preparing and measuring its nonclassical motion. For the first time, we will undertake laboratory tests of theoretical models for macroscopic wavefunction collapse. This will be possible even when the system is not in the ground state. The very low noise and high mechanical Q of this oscillator system also offers significant promise for sensing applications. Therefore as part of this research programme we will begin to explore these more classical applications which includes the development of a new type of in-trap spectrometer capable of measuring mass, charge and shape of nanoparticles, while another strand will seek to use the tunable interactions between the levitated particle for controlling, switching and storing light fields.
The Rationale: We need freshwater for agriculture, industry and human existence. Access to good quality water is essential for sustainable socio-economic growth. Freshwater ecosystems are finite and globally threatened by increasing environmental degradation caused by destructive land-use and water-management practices and increasing industrialization. The scale of socio-economic activities, urbanisation, industrial operations and agricultural practices in India has reached the point where watersheds across India are being severely impacted. For example, gross organic pollution in India's freshwater resources are common place, resulting in severe toxic burdens, depletion of dissolved oxygen levels and severe pathogenic contamination. Eutrophication, arising from enrichment with nutrients caused by sewage and agro-industrial effluents and agricultural run-off, greatly impact on lakes and impounded rivers. Groundwater bodies are susceptible to leaching from waste dumps, mining and industrial discharges. Finally, despite their potential threat, the distribution, scale and levels of newly emerging water contaminants, e.g. endocrine disrupting chemicals (EDCs), are largely unknown. We must address the consequences of both present and future contaminant threats to water catchments if we are to provide action that provide solutions at all levels. The implementation of sensors for monitoring important biological and chemical parameters, through time and space, is the indispensable basis for accurate assessments whilst the deployment of state-of-the-art water treatment technologies for the removal of pollutants will enhance water protection and security. The Proposition: Firstly; improve our ability to determine the presence of pollution in water courses and the development of novel sensing approaches to help reduce or prevent pollution at source. We will do this via; The deployment and implementation of new in situ fluorescence sensors that have been developed by UWE, Bristol and Chelsea Technology Group (CTG) as part of a current NERC Grant (NE/K007572/1) The development of a novel bacterial bio-sensor using bio-reporter strains that was first conceived in India (Bose Institute), for the detection of endocrine disrupting chemicals in water bodies and effluents. Secondly; develop novel approaches to reduce or prevent pollution detected above at the source via; The development of novel off-grid treatment technologies, for rural and urban areas, to remove pollutants (sensed above) based on ultrafiltration membrane technology and bacterial remediation using bio-reactors. Longer-term Impact: To understand the impact of sewage contamination and the bacterial quality of freshwater catchments in India. To quantify changes in sewage contamination levels through time and space and to understand how these changes are affected by land use and effluent discharges. Our fluorescence sensor will be used to identify, monitor and detect bacterial contamination from sewage discharges entering waters at a catchment scale, including urbanised areas. To develop a bacterial sensor, using bio-reporter strains, for the detection of endocrine disrupting chemicals in discharges and freshwaters. We will also assess the feasibility of the catabolic potential of these biosensor strains for bioreactor-based remediation of EDCs and implement an off-grid UF membrane technology platform for the treatment of bacterial contamination. This UK/India partnership will involve the deployment of UK developed technologies in India and the subsequent development of Indian inspired sensors and treatment approaches in the UK.