Csaba Mate Józsa

Learn More
Electronic transport in single or a few layers of graphene is the subject of intense interest at present. The specific band structure of graphene, with its unique valley structure and Dirac neutrality point separating hole states from electron states, has led to the observation of new electronic transport phenomena such as anomalously quantized Hall(More)
  • M Van Kampen, C Jozsa, +4 authors B Koopmans
  • Physical review letters
  • 2002
A novel, all-optical method to excite and detect spin waves in magnetic materials is presented. By exploiting the temperature dependence of the magnetic anisotropy, an ultrashort laser pulse is efficiently converted in a picosecond "anisotropy field" pulse that triggers a coherent precession of the magnetization. Recording the temporal evolution of the(More)
Spin relaxation in graphene is investigated in electrical graphene spin valve devices in the nonlocal geometry. Ferromagnetic electrodes with in-plane magnetizations inject spins parallel to the graphene layer. They are subject to Hanle spin precession under a magnetic field B applied perpendicular to the graphene layer. Fields above 1.5 T force the(More)
We studied the drift of electron spins under an applied dc electric field in single layer graphene spin valves in a field-effect transport geometry at room temperature. In the metallic conduction regime (n approximately 3.5 x 10(16) m(-2)), for dc fields of about +/- 70 kV/m applied between the spin injector and spin detector, the spin valve signals are(More)
The lattice reduction (LR) technique has become very important in many engineering fields. However, its high complexity makes difficult its use in real-time applications, especially in applications that deal with large matrices. As a solution, the modified block LLL (MB-LLL) algorithm was introduced, where several levels of parallelism were exploited: (a)(More)
In low-rate UWB impulse radio the carrier pulses have very short duration that limits the energy per bit in an extremely low value. The low bit energy results in an unacceptable short radio coverage. In the paper new UWB carrier pulse generation techniques are proposed to increase the pulse duration considerably. In order to get an ultra wideband carrier a(More)