Magnetic Bloch Oscillations in Nanowire Superlattice Rings

The recent growth of semiconductor nanowire superlattices encourages hope that Bloch-like oscillations in such structures formed into rings may soon be observed in the presence of a time-dependent magnetic flux threading the ring. These magnetic Bloch oscillations are a consequence of Faraday’s law; the time-dependent flux produces an electromotive force around the ring, thus leading to the Bloch-like oscillations. In the spectroscopic domain, generalized Wannier-Stark states are found that are manifestations of the emf-induced localization of the states.

Figure 1

Probability density, $|g_n(t){|}^2$, as a function of $n$ and $\Omega t$ of a WS-like state for $\nu =0$, $\Delta /2\hslash \Omega =4.5$, and $N=10$ corresponding to a state primarily localized around unit cell $\nu =0$. Points have been connected as a guide to the eye. The importance of boundary conditions as a function of $\Omega t$ is evident.