University of Stuttgart

About: University of Stuttgart is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Laser & Finite element method. The organization has 27715 authors who have published 56370 publications receiving 1363382 citations. The organization is also known as: Universität Stuttgart.

High-Precision Nanoscale Temperature Sensing Using Single Defects in Diamond

Abstract: Measuring local temperature with a spatial resolution on the order of a few nanometers has a wide range of applications in the semiconductor industry and in material and life sciences. For example, probing temperature on the nanoscale with high precision can potentially be used to detect small, local temperature changes like those caused by chemical reactions or biochemical processes. However, precise nanoscale temperature measurements have not been realized so far owing to the lack of adequate probes. Here we experimentally demonstrate a novel nanoscale temperature sensing technique based on optically detected electron spin resonance in single atomic defects in diamonds. These diamond sensor sizes range from a micrometer down to a few tens of nanometers. We achieve a temperature noise floor of 5 mK/Hz(1/2) for single defects in bulk sensors. Using doped nanodiamonds as sensors the temperature noise floor is 130 mK/Hz(1/2) and accuracies down to 1 mK for nanocrystal sizes and therefore length scales of a few tens of nanometers. This combination of precision and position resolution, combined with the outstanding sensor photostability, should allow the measurement of the heat produced by chemical interactions involving a few or single molecules even in heterogeneous environments like cells.

Optical particle trapping with computer-generated holograms written on a liquid-crystal display.

Abstract: Computer-generated holograms written on a liquid-crystal display can be used to generate dynamic light fields of arbitrary shape. This method was used to simultaneously trap polystyrene particles laterally and to displace them independently of one another.

Blockchains for Business Process Management - Challenges and Opportunities

Abstract: Blockchain technology offers a sizable promise to rethink the way interorganizational business processes are managed because of its potential to realize execution without a central party serving as a single point of trust (and failure). To stimulate research on this promise and the limits thereof, in this article, we outline the challenges and opportunities of blockchain for business process management (BPM). We first reflect how blockchains could be used in the context of the established BPM lifecycle and second how they might become relevant beyond. We conclude our discourse with a summary of seven research directions for investigating the application of blockchain technology in the context of BPM.

A generic grid interface for parallel and adaptive scientific computing. Part II: implementation and tests in DUNE

Abstract: In a companion paper (Bastian et al. 2007, this issue) we introduced an abstract definition of a parallel and adaptive hierarchical grid for scientific computing. Based on this definition we derive an efficient interface specification as a set of C++ classes. This interface separates the applications from the grid data structures. Thus, user implementations become independent of the underlying grid implementation. Modern C++ template techniques are used to provide an interface implementation without big performance losses. The implementation is realized as part of the software environment DUNE (http://dune-project.org/). Numerical tests demonstrate the flexibility and the efficiency of our approach.

Field Theory of Electromagnetic Brain Activity.

Abstract: The brain is considered as a complex, physical, and open system that exhibits spatiotemporal behavior at various time and length scales. A necessary condition for this pattern forming character of the brain is a nonlinear dynamics and a spatial interconnection of its elements, the neurons. The functional behavior of the brain is encoded in these spatiotemporal structures and can, at least partly, be extracted from the dynamics of the macroscopic quantities measured by the EEG and MEG. According to synergetics [1], this extraction contains all the relevant information about the spatiotemporal behavior of the brain and has, in general, a small number of degrees of freedom. This idea has been formalized to the order parameter conceptbased on circular causality: The order parameters are determined and created by the cooperation of microscopic quantities, but at the same time the order parameters govern the behavior of the whole system. Based on this approach phenomenological models were set up in the past for different experiments in order to find evolution equations that describe the experimentally observed macroscopic dynamics [2].