In recent years nanotechnology went through a huge advancement. In the following years the miniaturization of electronic circuit components will reach the physical boundaries, therefore research focuses on conceptually new computation method, quantum computation. The basic building block is the qubit, which can be encoded for example in the spin of an electron trapped in a quantum dot. The manipulations of these qubits and the coupling between distant qubits can be done using high frequency techniques in the microwave regimes. The photons can be used rotate qubits, whereas the resonators can act as a quantum bus between two qubits.
The high frequency techniques are also important for the characterization on nano-circuits. These methods can be used to study relaxation processes, measure quantum capacitance and by using noise measurements the charge of quasi-particles or the non-equilibrium distribution functions can be obtained. Finally, high frequency reflectometry measurements allow fast and sensitive readout of conductance, even in cases where DC transport measurements cannot be used (like internal charge dynamics).
During the PhD work the candidate will be involved in the development of a new high-frequency setup, in the fabrication of superconducting nano-circuits. Using the high-frequency circuits quantum dots realized in semiconducting nanowires and graphene heterostructures will be studied. The circuits will be realized using electron-beam lithography and will be measured at ultra-low temperatures. The work is done in close collaboration with European universities.
|Left: Spin-qubit coupled to an RF resonator (artistic view). Right: Scanning electron image of a high frequency resonator (source: P. Makk, G. Fülöp)|
Knowledge of solid state physics, motivation for experimental work, English knowledge, basic programming and measurement automation skills.