Bartłomiej Szafran,
bszafran@agh.edu.pl,
D10/329, tel. 12 617 20 38 WFiIS AGH

Poszukiwany doktorant do projektu Preludium BIS w rekrutacji 2021/2022 do Szkoly Doktorskiej AGH

Electrostatic quantum dots in two-dimensional layers of black phosphorous

Opis zagadnienia badawczego: The proposed PhD project deals with theoretical description of electrostatic quantum dots defined in black phosphorous (BP) in few-layer and monolayer form (phosphorene). BP is a high carrier mobility material and the progress of electronics in BP is very fast, the field-effect-transistors that are stable in the room temperature and work close to the ballistic limit were reported in 2019. The energy gap in BP allows for electrostatic confinement that is excluded for graphene due to the Klein tunneling effect. In this project we aim to prepare a theoretical description of the properties of a charged systems confined in an electrostatic quantum dot in few-layer BP and phoshorene. The proposed topic contains new physics to be explored by the PhD student. A monolayer phosphorene is a puckered honeycomb lattice, with P atoms on two parallel planes. The crystal structure of monolayer and few-layer material is strongly anisotropic which is translated to the in-plane anisotropy of the electron stucture. The conduction and valence bands are strongly anisotropic near the gamma point with the effective masses along the zigzag direction are much larger than in the armchair direction. The anisotropy of the conductance and valence bands leads in particular to a nonregular structure of the Landau levels in the quantum Hall conditions. The heavy carrier masses – for the zigzag direction – should enhance the carrier-carrier interaction and produce strongly correlated phases (Wigner molecules, and FQHE states). The orientation of QD in space – which can be tuned by gate voltages – will determine the relative strength of the interaction. The transport spectroscopy is precise enough to resolve the energy effects of the spin-orbit interactions. Moreover, due to the puckered lattice the vertical electric field can change or close the energy gap which produces further prospects for manipulation of the confined states by electric fields.

This PhD thesis is supported by NCN Preludium BIS project that provides the scholarship of 5k PLN /month for first 24 months, and 6k PLN/month for next 24 months, plus 48k PLN for participation of the PhD student in conferences, and about 22k PLN for other expenses.

The recruitment for this project is OPEN. There is no default candidate for this position. Deadline for applications: 15.05.2021