Cryogenic Ultrafast Scattering-type Terahertz-probe Optical-pump Microscopy (CUSTOM)

点击翻译按钮获取中文摘要

Technology underpins our society and economy and devices are constantly evolving, becoming smaller, faster, and 'smarter'. However, current technologies are fast approaching their physical limit and suffer from high, inefficient power consumption and poor energy storage. Integrated photonic, electronic and quantum technologies have the potential to disrupt these existing technologies, providing '21st-century products' with improved performance including energy efficiency. These devices will have a broad range of applications and will impact several sectors, such as healthcare, defence and security, ICT, and clean energy. Advanced functional materials, including graphene, 2D materials and semiconductor nanostructures, are the building blocks of these devices with the potential to deliver a step-change in performance through exploitation of novel quantum effects. An in-depth understanding of their electronic, photonic and spintronic properties, and how they may be controlled, enhanced and exploited is therefore essential.Although several characterisation techniques exist it still remains difficult to obtain a complete picture of their optoelectronic/spintronic behaviour. Often a combination of methodologies are required to extract device parameters, such as charge carrier mobility and lifetime; and these techniques have their own limitations - they can be destructive, only perform ensemble measurements, or only operate at room temperature and ambient pressure. Notably, material characterisation remains challenging on nanometre length scales, with the majority of techniques limited in resolution to the micron scale. As the majority of devices rely on controlling and designing electronic behaviour at the nanoscale (e.g. pn junctions), nanoscale spatial resolution is essential for accelerating device development. There is therefore an urgent need for state-of-the-art research infrastructure that can provide nanometre spatial resolution and combine the strengths of current methodologies to investigate materials over a large parameter range.The proposed investment will establish a new national facility for advanced nanoscale material characterisation and will provide the 'missing tool' required to conduct simultaneous imaging and spectroscopy at 3 extremes: ultrafast (<1ps) timescales, nanoscale (<30nm) length scales, and low temperatures (<10K). By combining ultrafast THz and midinfrared (MIR) spectroscopy with cryogenic scattering-type near-field optical microscopy, this facility will provide an exclusive tomographic tool that allows surface-sensitive, non-destructive optoelectronic characterisation of individual nanomaterials over a temperature range of 4.2-300K. As the THz and MIR frequency range encompasses the energy range of several fundamental quasiparticles (e.g. plasmons, free electrons and holes, and magnons), this capability will open up a new parameter range for investigating low-energy excitations in advanced functional materials, including III-V nanowires, 2D materials, topological insulators, and chalcogenides. It will allow differential depth-profiling and 3D mapping of the local dielectric function, electrical conductivity, chemical composition, stress/strain fields with <30nm spatial resolution, and enable investigation of nanoscale photoinduced carrier dynamics and ultrafast vibrational dynamics with <1ps temporal resolution. The facility will be unique to the UK/EU and will provide unprecedented capability for advanced functional materials research. Access to the tool will be made available to UK academics and industry undertaking research in this area. The system will be housed within the UK National Laboratory for Advanced Materials (the Henry Royce Institute) at the University of Manchester and will link with other key materials research infrastructure, such as P-NAME and Royce MBE systems, to form a key chain in the feedback loop between materials optimisation and device development.