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We demonstrate the key features of an interference cathode using both simulations and experiments. We deposit Cs3Sb photocathodes on Ag to produce an interference enhanced photocathode with 2–5× quantum efficiency (QE) enhancement using a robust procedure that requires only a smooth metal substrate and QE monitoring during growth. We grow both an interference cathode (Ag substrate) and a typical photocathode (Si reference substrate) simultaneously to confirm that the effects are due to optical interactions with the substrate rather than photocathode composition or surface electron affinity differences. Growing the cathodes until the QE converges shows both the characteristic interference peaks during growth and the identical limiting case where the cathode is “infinitely thick,” in agreement with simulations. We also grow a cathode until the QE on Ag peaks and then stop the growth, demonstrating broadband QE enhancement.

A high-throughput, operando-ready X-ray absorption spectroscopy catalytic reaction cell consisting of 4 parallel reactors was designed to collect X-ray absorption near edge structure and extended fine structure spectra under reaction conditions. The cell is capable of operating at temperatures from ambient conditions up to 773 K and pressures from ambient to 2 MPa in a variety of gas environments. The cell design is mechanically simple, and programmable operation at beamline 8-ID (NSLS-II, Brookhaven National Laboratory) makes it straightforward to use. Reactor tube parts were available as-fabricated from commercial sources, while the heating jacket and cell mounting required custom machining.

A novel miniature (∼2×2×1 mm) dielectric resonator for X-band electron paramagnetic resonance experiments is presented. The resonator is based on a single crystal of KTaO3, which is excited to its TE01δ resonance mode by means of a simple iris-screw coupling. Several configurations of resonators are considered and discussed with respect to their filling factor, power conversion ratio, and optical excitation efficiency. Our findings are presented in terms of both experimental and theoretical studies. For small samples, the high filling factor of this resonator results in a signal increase by a factor of 140–800 (assuming nonsaturating conditions) as compared to a rectangular X-band cavity. The high power conversion factor (∼40 G/W), should enable one to perform pulse experiments employing power amplifiers, with ∼100-fold less peak power used for rectangular cavities. With an antireflective layer, the crystal’s transparency enables efficient laser illumination of the sample in light-induced experiments.