Andreas Pedersen - Space Charge Induced Charge-density Modulation
Fyrirlesturinn verður haldinn fimmtudaginn 12. nóvember kl. 13:30 í húsnæði Háskólans í Reykjavík, Kringlunni 1 (gamla Mbl húsinu) í stofu K-5.
Andreas Pedersen
Háskólinn í Reykjavík, nýdoktor
Abstract:
The Child-Langmuir equation has served as a valuable tool to describe the maximal current through a vacuum diode for a long time. However, as it is restricted to the 1D-continuous case, it cannot account for effects caused by the point-like nature of the electron. In a series of simulations where electrons are treated as point-charges we address and analyze these effects in a µm-scale vacuum diode. Our main finding is that a pulsed signal is obtained rather than a continuous maximal current, and that the frequency of this pulsed signal is determined by the applied potential. The explanation for this behavior can be found in the emission process of electrons, which is determined by the conditions of the E-field at the surface of the cathode.
