Publications by authors named "Aleksandr Y Kuntsevich"

This paper presents a home-built projection lithographer designed to transfer the image from a DLP (digital light processing) projector MEMS matrix onto the microscope objective's field of view, where a photoresist-covered substrate is placed. The photoresist is exposed using blue light with a wavelength of 450 nm. To calibrate the device and adjust focal lengths, we utilize a red light that does not affect the photoresist.

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Article Synopsis
  • The study explores the mechanical properties of layered crystals with a focus on hBN/WSe/hBN heterostructures, using a specialized ultrasonic technique for detailed analysis.
  • A picosecond measurement method analyzes the temporal changes in reflection coefficients after laser pulse excitation, allowing for the detection of sound waves reflecting off various layers within the structure.
  • The findings highlight the low phonon dissipation in these materials below 150 GHz, indicating their promise for applications in nanotechnology and acoustics.
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Search for doped superconducting topological insulators is of prime importance for new quantum technologies. We report on fabrication of Sr-doped Bi2Te3 single crystals. We found that Bridgman grown samples have -type conductivity in the low 1019 cm-3, high mobility of 4000 cm2V-1s-1, crystal structure independent on nominal dopant content, and no signs of superconductivity.

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The fast and precise fabrication of micro-devices based on single flakes of novel 2D materials and stacked heterostructures is vital for exploration of novel functionalities. In this paper, we demonstrate a fast high-resolution contact mask lithography through a simple upgrade of metallographic optical microscope. Suggested kit for the micromask lithography is compact and easily compatible with a glove box, thus being suitable for a wide range of air-unstable materials.

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Van-der Waals heterostructures assembled from one or few atomic layer thickness crystals are becoming increasingly more popular in condensed matter physics. These structures are assembled using transfer machines, those are based on mask aligners, probe stations or are home-made. For many laboratories it is vital to build a simple, convenient and universal transfer machine.

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In this study, we grew Cu co-doped single crystals of a topological superconductor candidate Sr x Bi 2 Se 3 , and studied their structural and transport properties. We reveal that the addition of even as small an amount of Cu co-dopant as 0.6 atomic %, completely suppresses superconductivity in Sr x Bi 2 Se 3 .

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