| Özet: | We report the development of a continuous-wave and pulsed X-band electron spin resonance (ESR) spectrometer for
the study of spins on ordered surfaces down to cryogenic temperatures. The spectrometer operates in ultra-high vacuum
and utilizes a half-wavelength microstrip line resonator realized using epitaxially grown copper films on single crystal
Al2O3 substrates. The one-dimensional microstrip line resonator exhibits a quality factor of more than 200 at room
temperature, close to the upper limit determined by radiation losses. The surface characterizations of the copper strip
of the resonator by atomic force microscope, low-energy electron diffraction, and scanning tunneling microscope show
that the surface is atomically clean, flat, and single crystalline. Measuring the ESR spectrum at 15 K from a few
nm thick molecular film of YPc2, we find a continuous-wave ESR sensitivity of 2.6 · 1011 spins/G · Hz1/2
indicating
that a signal-to-noise ratio of 3.9 G · Hz1/2
is expected from a monolayer of YPc2 molecules. Advanced pulsed ESR
experimental capabilities including dynamical decoupling and electron-nuclear double resonance are demonstrated
using free radicals diluted in a glassy matrix.
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