YSFOP2018 | 国内外顶级青年才俊齐聚光谷，共享一场光电子思想盛宴
演讲主题：The multifaceted world of photonic crystal fibres
演讲摘要: The idea for a new kind of optical glass fibre—photonic crystal fibre (PCF)—first emerged in 1991. The aim was to realise a fibre with a two-dimensional periodic array of microscopic features (typically hollow channels) running along its entire length. These would be able to corral light within a central hollow or solid core, permitting light and matter waves to be tightly confined over long distances while precisely controlling the dispersion. More than a quarter of a century later, PCF has led to a whole series of new developments, some of which are already are moving into real-world applications. Solid-core PCFs are routinely used to transform invisible infrared laser pulses into white light 10 million times brighter than an arc lamp, and form the basis of commercial supercontinuum sources. Twisted PCF creates optical vortices that carry orbital angular momentum, as well as providing an elegant means of providing circular birefringence and dichroism. Intense interactions between light and sound in solid-core PCF enable stable all-optical mode-locking of fibre lasers at a high harmonic (a few GHz) of their round-trip frequency. Single-ring hollow-core PCF, comprising a ring of thin-walled capillaries surrounding a central hollow core, guides over an extremely wide frequency range and, through pressure-adjustable dispersion, provides a simple means of compressing pulses down to single-cycle durations, as well as underpinning a range of unique and extremely bright sources of tunable deep and vacuum ultraviolet light.
University of Eastern Finland
演讲主题：Measurement of spectral coherence Stokes parameters
演讲摘要: Compared with the traditional time-domain analysis the frequency-domain representation of random light is beneficial in situations involving light-matter interactions or broadband light. In the context of scalar fields it is known that the spectral degree of spatial coherence can be obtained by first narrowband filtering the light and then observing the visibility and position of the intensity fringes in the immediate vicinity of the optical axis in Young’s interferometer, i.e., detecting the equal-time degree of spatial coherence of the filtered light at the apertures. It has also been found that filtering does not alter the spectral degree of coherence and that the filtered light is crossspectrally pure. It also follows that the fringe visibility does not increase (change) if the filter passband is decreased, which was experimentally verified in. Our work generalizes the above results into the electromagnetic domain.
University of North Carolina at Charlotte
演讲主题：Orbital angular momentum in partially coherent vortex beams
演讲摘要: Light beams possessing orbital angular momentum (OAM) have become an important tool in a wide variety of applications, including free-space optical communications and optical micromanipulation. Most studies have considered the fully coherent case; however, partially coherent beams offer increased flexibility in the design of and control of orbital angular momentum in light fields. In this talk we discuss three broad and distinct classes of angular momentum-carrying beams, and from insights gained introduce a fourth, twisted vortex Gaussian Schell-model beams, which possess two different types of OAM.
University of Vienna
演讲主题：Using quantum photonics to probe quantum foundations
演讲摘要：The promise of quantum computation and cryptography has led to the development of many new quantum technologies, and has resulted in techniques to efficiently create, detect, and manipulate delicate quantum systems. An exciting aspect of this is that we are now able to perform experiments that not too long ago could only be imagined as “gedanken” experiments. This now allows us to use table-top experiments to probe foundational aspects of quantum mechanics. In this talk I review our progress in experimental quantum optics, and some of our recent work in quantum foundations. On the foundations side, I will introduce the notion of a causal order, and show that it is possible to create quantum processes which possess a genuinely undefined causal order.
Johannes Kepler University Linz
演讲主题：Semiconductor quantum dots for quantum photonics applications
演讲摘要: Semiconductor quantum dots (QDs) obtained by epitaxial growth are regarded as one of the most promising solid-state sources of triggered single and entangled photons for applications in emerging quantum communication and photonic quantum-information-processing. In this talk, I will introduce the “features and bugs” of QDs in view of their potential applications, followed by a presentation of some of our recent results.
演讲主题：Mid-infrared fibre laser technology
演讲摘要: The mid-infrared region of the electromagnetic spectrum (2-20 μm) has attracted significant scientific and technological interest as all molecules have their ro-vibrational absorption lines in this wavelength range. Therefore, the mid-IR is usually referred to as the ‘molecular fingerprint’ region. Owing to the high-impact applications that result from the strong molecule-photon interaction, such as trace molecular detection for airport security screening and non-invasive breath analysis, research in mid-IR lasers and photonics has become one of the hottest topics in modern optics research over the last few years.
In this talk I will summarise our recent scientific breakthroughs towards the development of all-fibre laser sources based on fluoride-glass optical fibres. In particular I will focus on the direct femtosecond laser-inscription of in-fibre components like Bragg gratings and polarisers as well as on the generation of an ultrabroadband supercontinuum in the mid-IR via nonlinear spectral broadening in hybrid chalcogenide/polymer microwires.
演讲主题：Toward quantum supremacy using solid-state single photons
演讲摘要: Boson sampling is considered as a strong candidate to demonstrate the “quantum advantage / supremacy” over classical computers. However, previous proof-of-principle experiments suffered from small photon number and low sampling rates owing to the inefficiencies of the single-photon sources and multi-port optical interferometers. In this talk, I will report two routes towards building Boson Sampling machines with many photons.
演讲主题：Manipulating spatial coherence structure of partially coherent beam and its applications
演讲摘要: High coherence is an important properties of laser beam, while laser beam with low spatial coherence (i.e., partially coherent beam) is preferred in many applications, such as free-space optical communications, ghost imaging, remote sensing, and so on. The spatial coherence structure of conventional partially coherent beam is of Gaussian distribution. Partially coherent beam with nonconventional coherence structure exhibits many novel properties, such as self-focusing, self-shaping, self-splitting and self-reconstruction, and is useful for optical manipulation, beam shaping, sub-Rayleigh imaging, information transfer and orbital angular momentum measurement. In this talk, I will introduce recent development on manipulating spatial coherence structure of partially coherent beam and its applications.
演讲主题：Ultrafast Laser Spectroscopy of Lead Halide Perovskites: Fundamentals
演讲摘要: Recent years have witnessed a tremendous success in the field of solar cells and LED with lead halide perovskite. Here we investigate the fundamental excited state dynamics in different forms of perovskite using ultrafast spectroscopy technique. We show that at high excitation intensity, the auger recombination in perovskite quantum dots (QDs) exhibits a two-order exciton-exciton annihilation instead of the common three-order one, which will reduce the nonradiative loss of carriers and benefit applications such as LED and laser. Furthermore, thanks to the excellent optical property of perovskite QDs, light utilization in monolayer transition metal dichalcogenides (TMDCs) is increased larger than 10 times through constructing perovskite QDs/TMDCs heterostructures. Finally, the 2D/3D hybrid perovskite has been investigated. Energy transfer and carrier transfer has been found to be coexistent, whose efficiency is promoted by the strong interlayer coupling of the different perovskite phases and thus can be utilized to address high performance device for both light-emitting and light-harvesting applications under certain architecture.