  The present dissertation covers two related research projects. The first
topic was initiated with the ultimate goal of observing quantum degeneracy in
ultrashort free electron pulses. This constitutes a thorough theoretical
analysis of the problem involving partial quantum coherence and spin
polarization of the source in light of a path-integral treatment of the
phenomenon of matter-wave diffraction-in-time. Subsequently, results of a
trailblazing experiment, to be superseded by a Hanbury Brown-Twiss type
conclusive test of free fermion antibunching with electrons, is reported. In
this experiment, the statistical distribution of the emitted electrons is
studied taking advantage of a double-detector coincidence detection technique.
The utilized electron emitters are ultrafast photoemission tungsten nanotip
needle sources which are known to procure large spatial coherence lengths. The
emission statistics is found to be sub-Poissonian. The second project involves
introduction and full characterization of a novel laser-driven electron nanotip
emitter based on metallized fiber optic tapers in which the emission mechanism
is found to be assisted by surface plasmon resonance excitation as predicted
prior to the design of such sources. It is shown that gold-coated fiber optic
nanotips can emit electrons using both low-power continuous wave lasers as well
as femtosecond pulsed lasers tuned to or near the surface plasmon resonance
excitation wavelength of the system. The final chapter entails a proposal of a
spin-polarized electron photoemitter based on the spin Hall effect for which
such a fiber optic nanotip source is exploited.
