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In this work, we report our method of fabricating nanoscale multilayered Bi₂Te₃/Sb₂Te₃ thin film-based integrated thermoelectric devices, and detail the voltage and power produced by the device. The multilayered Bi₂Te₃/Sb₂Te₃ thin film was grown via e-beam evaporation; it had 20 alternating Bi₂Te₃- and Sb₂Te₃-layers, each layer being 1.5 nm thick. We characterized the film using high-resolution transmission electron microscopy (HRTEM), revealing its excellent cross-sectional structure without any obvious interface defects. The Bi₂Te₃/Sb₂Te₃ multilayer films were investigated by synchrotron x-ray scattering. An integrated device including 128×256 thermoelectric elements was fabricated from the multilayered film. An open-circuit voltage of 51 mV andmore » a maximum power of 21 nW were produced from this 30 nm-thick Bi₂Te₃/Sb₂Te₃ multilayer TE device. We found that the nanoscale multilayer structure significantly affects the voltage and power produced. Lastly, the fabrication of the integrated thermoelectric devices is compatible to that of generating standard integrated circuits (ICs), and is scalable for producing higher voltage and power, or achieving solid-state cooling for on-chip applications.« less

A thin-glass-shell, D³He-filled exploding-pusher inertial confinement fusion implosion at the National Ignition Facility (NIF) has been demonstrated as a proton source that serves as a promising first step toward development of a monoenergetic proton, alpha, and triton backlighting platform at the NIF. Among the key measurements, the D3He-proton emission on this experiment (shot N121128) has been well-characterized spectrally, temporally, and in terms of emission isotropy, revealing a highly monoenergetic (ΔE/E~4%) and isotropic source (~3% proton fluence variation and ~0.5% proton energy variation). On a similar shot (N130129, with D₂ fill), the DD-proton spectrum has been obtained as well, illustrating thatmore » monoenergetic protons of multiple energies may be utilized in a single experiment. In conclusion, these results, and experiments on OMEGA, point toward future steps in the development of a precision, monoenergetic proton, alpha, and triton source that can readily be implemented at the NIF for backlighting a broad range of high energy density physics (HEDP) experiments in which fields and flows are manifest, and also utilized for studies of stopping power in warm dense matter and in classical plasmas.« less

Measurements of yield, ion temperature, areal density (ρR), shell convergence, and bang time have been obtained in shock-driven, D₂ and D³He gas-filled “exploding-pusher” inertial confinement fusion (ICF) implosions at the National Ignition Facility to assess the impact of ion kinetic effects. These measurements probed the shock convergence phase of ICF implosions, a critical stage in hot-spot ignition experiments. The data complement previous studies of kinetic effects in shock-driven implosions. Ion temperature and fuel ρR inferred from fusion-product spectroscopy are used to estimate the ion-ion mean free path in the gas. A trend of decreasing yields relative to the predictions ofmore » 2D draco hydrodynamics simulations with increasing Knudsen number (the ratio of ion-ion mean free path to minimum shell radius) suggests that ion kinetic effects are increasingly impacting the hot fuel region, in general agreement with previous results. Lastly, the long mean free path conditions giving rise to ion kinetic effects in the gas are often prevalent during the shock phase of both exploding pushers and ablatively driven implosions, including ignition-relevant implosions.« less

A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D³He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D³He-proton signal-to-background by a factor ofmore » 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D3He-filled surrogate implosions at the NIF.« less