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We develop a self-supervised ensemble learning (SSEL) method to accurately classify distinct types of phase transitions by analyzing the fluctuation properties of machine learning outputs. Employing the 2D Potts model and the 2D Clock model as benchmarks, we demonstrate the capability of SSEL in discerning first-order, second-order, and Berezinskii-Kosterlitz-Thouless transitions, using in-situ spin configurations as the input features. Furthermore, we show that the SSEL approach can also be applied to investigate quantum phase transitions in 1D Ising and 1D XXZ models upon incorporating quantum sampling. We argue that the SSEL model simulates a special state function with higher-order correlations between physical quantities, and hence provides richer information than previous machine learning methods. Consequently, our SSEL method can be generally applied to the identification/classification of phase transitions even without explicit knowledge of the underlying theoretical models.

In this paper, a practical micromachining technology was applied for the fabrication of a micro probe using a complex nontraditional machining process. A series process was combined to machine tungsten carbide rods from original dimension. The original dimension of tungsten carbide rods was 3mm ; the rods were ground to a fixed-dimension of 50 micrometers using precision grinding machine in first step. And then, the rod could be machined to a middle-dimension of 20 micrometers by electrolysis. A final desired micro dimension can be achieved using supersonic aided electrolysis. High-aspect-ratio of micro tungsten carbide rod was easily obtained by this process. Surface roughness of the sample with supersonic aided agitation was compared with that with no agitation in electrolysis. The machined surface of the sample is very smooth due to ionized particles of anode could be removed by supersonic aided agitation during electrolysis. Deep micro holes can also be achieved by the machined high-aspect-rati tungsten carbide rod using EDM process. A micro probe of a ball shape at the end was processed by proposed supersonic aided electrolysis machining process., Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838)

Brominated Thornel P-100 carbon fibers are found to be intercalated, as shown by Raman scattering. X-ray diffraction and electron diffraction show that the bromine layers in the fibers are disordered at room temperature, even though all previously reported graphite-bromine phases exhibit inplane superlattice ordering at room temperature. A new phase transition at 271 K was observed by differential scanning calorimetry, electron diffraction, and the variation of the electrical resistivity with temperature; it corresponds to the reversible change between inplane disorder above 271 K to inplane superlattice order below 271 K. The 240 cm−1 intercalate Raman peak at room temperature is much broader than that of previously reported graphite-bromine, indicating more nonuniformity in intercalate structure in the fibers. The chemical interaction between bromine and the fibers is similar to that between bromine and graphite, as shown by the increase of the bromine desorption rate at 100°C upon heating for both fibers and graphite and the decrease of the electrical resistivity by bromination in fibers as well as graphite. No evidence for bulk bromine in the fibers was obtained.