Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Time-diffraction and Zitterbewegung of two-dimensional massless Dirac
  excitations   We explore the dynamics of two-dimensional massless Dirac-fermions within a
quantum shutter approach, which involves the time-evolution of an initial
cut-off plane wave. We show that the probability density is governed by an
interplay between {\it diffraction in time} and {\it Zitterbewegung} phenomena,
typical of relativistic quantum shutter systems with nonzero mass. The {\it
time-diffraction} appears as an oscillatory pattern in the probability density,
similar to the effect predicted by Moshinsky in 1952 [Phys. Rev. \textbf{88},
625] for Schr\"odinger free matter-waves. The {\it Zitterbewegung} manifests
itself as high-frequency oscillations embedded in the time-diffraction profile.
We found that these two transient effects are induced by the transverse
momentum component of the incident wave, $k_y$, that acts as an effective mass
of the system. Furthermore, this effective mass can be manipulated by tuning
the incidence angle of the initial quantum state, which allows to control the
frequencies of the transients. In particular, we demonstrate that near a normal
incidence condition, the {\it Zitterbewegung} appears as a series of {\it
quantum beats} in the probability density, with a beating frequency $2k_yv_F$,
where $v_F$ is the Fermi velocity.

9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn