Results found: 3

Number of results on page

Search results

Sort By:

Limit search:

Quantum Spin Hall Effect in Strained (111)-Oriented SnSe Layers

100%

Safaei S., Galicka M., Kacman P., Buczko R.

Acta Physica Polonica A

2016

vol. 129

issue 1a

A-150-A-152

Recently, the quantum spin Hall effect has been predicted in (111)-oriented thin films of SnSe and SnTe topological crystalline insulators. It was shown that in these films the energy gaps in the two-dimensional band spectrum depend in an oscillat ory fashion on the layer thickness - the calculated topological invariant indexes and edge state spin polarizations show that for films 20-40 monolayers thick a two-dimensional topological insulator phase appears. Edge states with the Dirac cones with opposite spin polarization in their two branches are obtained for both materials. However, for all but the (111)-oriented SnTe films with an even number of monolayers an overlapping of bands in Γ̅ and M̅ diminishes the final band gap and the edge states appear either against the background of the bands or within a very small energy gap. Here we show that this problem in SnSe films can be removed by applying an appropriate strain. This should enable observation of the quantum spin Hall effect also in SnSe layers.

Modeling of Small Diameter Semiconductor Nanowires

100%

Bukała M., Galicka M., Buczko R., Kacman P.

Acta Physica Polonica A

2007

vol. 112

issue 2

425-430

The properties of very thin (up to 16Å diameter) wires, cut out from the bulk in either zinc-blende or wurtzite material, are studied theoretically. In the total energy calculations we use ab initio methods and consider three different crystallographic growth axes for the zinc-blende and one for the wurtzite structure. We show that the most stable zinc-blende nanowires are those growing along (111) direction, however, the wurtzite structure is found to be energetically more favorable than the zinc-blende for wires of the same diameter. In addition, the band structure of the wires was calculated.

Experimental and Theoretical Analysis οf PbTe-CdTe Solid Solution Grown by Physical Vapour Transport Method

52%

Szot M., Szczerbakow A., Dybko K., Kowalczyk L., Smajek E., Domukhovski V., Łusakowska E., Dziawa P., Mycielski A., Story T., Bukała M., Galicka M., Sankowski P., Buczko R., Kacman P.

Acta Physica Polonica A

2009

vol. 116

issue 5

959-961

Bulk monocrystals of Pb_{1-x}Cd_{x}Te, with the Cd content x up to 0.11, were grown by physical vapour transport method. The structural, electrical and optical properties of these ternary crystals were studied experimentally and theoretically. All investigated samples exhibit rock-salt structure and high crystal quality, which was confirmed by X-ray rocking curve width parameter of about 100 arcsec. The decrease of the lattice parameter with increasing Cd content x was found experimentally, in agreement with ab initio calculations. The band structures of Pb_{1-x}Cd_{x}Te mixed crystals for x values up to 0.2 were calculated using tight binding approach. The calculated band gap in the L-point increases with the Cd content in qualitative agreement with photoluminescence measurements in the infrared. For all studied Pb_{1-x}Cd_{x}Te samples, the Hall effect and electrical conductivity measurements, performed in the temperature range from 4 to 300 K, revealed p-type conductivity.

Refine search results

3 Acta Physica Polonica A

1 2016

1 2009

1 2007

3 Buczko R.

3 Galicka M.

3 Kacman P.

2 Bukała M.

1 Domukhovski V.

1 Dybko K.

1 Dziawa P.

1 Kowalczyk L.

1 Mycielski A.

1 Safaei S.

1 Sankowski P.

1 Smajek E.

1 Story T.

1 Szczerbakow A.

1 Szot M.

1 Łusakowska E.

Search results

Quantum Spin Hall Effect in Strained (111)-Oriented SnSe Layers

Modeling of Small Diameter Semiconductor Nanowires

Experimental and Theoretical Analysis οf PbTe-CdTe Solid Solution Grown by Physical Vapour Transport Method