Quantum computing at landau levels in nanographite films

Visualization of the pseudomagnetic field in nanographite films using optical radiation from Landau levels significantly simplifies magnetic field detection compared to the proposal by the authors, who used a scanning tunneling microscope at a temperature of 7.5 K to visualize Landau levels. In our case, optical radiation measurements from Landau levels were conducted using a photodiode at room temperature. The existence of a stable Landau level staircase in nanographite films opens the possibility of quantum computing on Landau level qubits.  For the standard scanning tunneling microscope qubit with the frequency 4.3 GHz, one obtains the value the Josephson energy 6,58×10-24 J. That is the cryogenic cooling up to 20 mK is required. For the nanographite film Josephson’s frequency of about 424 GHz, which is 42 times higher than the one for standard Josephson qubits, which allows for a two-order-of-magnitude increase in information processing speed compared to a standard scanning tunneling microscope qubit.