Research

The main research task of our team is the growth of low dimensional structures: nanowires, quantum dots, quantum wells composed of II-VI semiconductors and their structural and chemical characterization including optical properties of individual nano-objects. Recently, our research interest is broadened by fabrication and optical properties of two-dimensional (2D) materials: indium selenide, molybdenum diselenide, antimony triselenide.

The basic method for the fabrication of nanostructures is the molecular beam epitaxy (MBE). Our team disposes of two MBE setups coupled under high vacuum: EPI 620 equipped with Te, Cd, Zn, Mn, Mg, I effusion cells and nitrogen RF plasma source and PREVAC equipped with Se, Zn, Cd, Pb, Sb, In effusion cells and electron gun for the deposition of Mo, Co and Au.

The most important nanostructures grown in our laboratory:

• 2D Materials: indium selenide, molybdenum diselenide antimony triselenide
• Nanowires: CdTe, ZnTe, (Cd,Mn)Te, (Zn,Mn)Te, (Cd,Mg)Te, (Zn,Mg)Te,
• Nanowire heterostructures
  • Radial core/shell nanowires: ZnTe/(Zn,Mg)Te, CdTe/(Cd,Mg)Te,
  • Axial nanowire quantum dots: CdTe/ZnTe, ZnTe/(Zn,Mg)Te
• Quantum dots: CdTe/ZnTe, Cd(Se,Te)/ZnTe, (Cd,Mn)Te/ZnTe
• Quantum wells CdTe/(Cd,Mg)Te with 2D electron gas obtained due to iodine modulation doping within the barrier

Methods of nanostructure investigation:

• Low temperature cathodoluminescence: HCLUE system by Horiba for UV-VIS and NIR spectral range, low temperature stage by Kammrath & Weiss (10 – 300 K)
• Micro-photoluminescence
• Scanning electron microscope: Zeiss Auriga
• Chemical composition study by means of EDS detector (by Bruker)