We report on physical mechanisms behind the temperature-dependent optical absorption, photoluminescence (PL), and photoconductivity in spin-coated films of a functionalized anthradithiophene (ADT) derivative, ADT-triethylsilylethynyl (TES)-F, and its composites with C₆₀ and another ADT derivative, ADT-TIPS-CN. Measurements of absorption and PL spectra, PL lifetimes, and transient photocurrent were performed at temperatures...
Studies of light-matter interactions in organic semiconductors and in optical tweezer trapping of nanoparticles are presented. In the research related to organic semiconductor materials, a variety of novel materials and their composites have been characterized, and physical mechanisms behind their optoelectronic properties have been established. Three novel functionalized hexacene derivatives...
We present a model that describes nanosecond (ns) time-scale photocurrent dynamics in functionalized anthradithiophene (ADT) films and ADT-based donor-acceptor (D/A) composites. By fitting numerically simulated photocurrents to experimental data, we quantify contributions of multiple pathways of charge carrier photogeneration to the photocurrent, as well as extract parameters that characterize charge...
The Antarctic contribution to sea level is a balance between ice loss along the margin and accumulation in the interior. Accumulation records for the past few decades are noisy and show inconsistent relationships with temperature. We investigate the relationship between accumulation and temperature for the past 31 ka using high-resolution records...
Full Text:
, Christo Buizert3, Kendrick Taylor4, Eric J. Steig1,
Edwin Waddington1, Howard Conway1, Michelle Koutnik1
The Antarctic contribution to sea level is a balance between ice loss along the margin and accumulation in the interior. Accumulation records for the past few decades are noisy and show inconsistent relationships with temperature. We investigate the relationship between accumulation and temperature for the past 31 ka using high-resolution records...
Full Text:
temperature in West Antarctica
for the past 31,000 years
T. J. Fudge1, Bradley R. Markle1, Kurt M. Cuffey2
The Antarctic contribution to sea level is a balance between ice loss along the margin and accumulation in the interior. Accumulation records for the past few decades are noisy and show inconsistent relationships with temperature. We investigate the relationship between accumulation and temperature for the past 31 ka using high-resolution records...
We present a new high-precision, high-resolution record of atmospheric methane from the West Antarctic Ice Sheet (WAIS) Divide ice core covering 1000–1800 C.E., a time period known as the late preindustrial Holocene (LPIH). The results are consistent with previous measurements from the Law Dome ice core, the only other high-resolution...
One common assumption in interpreting ice-core CO₂ records is that diffusion in the ice does not affect the concentration profile. However, this assumption remains untested because the extremely small CO₂ diffusion coefficient in ice has not been accurately determined in the laboratory. In this study we take advantage of high...
We report a decadally resolved record of atmospheric CO₂ concentration for the last 1000 years, obtained from the West Antarctic Ice Sheet (WAIS) Divide shallow ice core. The most prominent feature of the pre-industrial period is a rapid ∼7 ppm decrease of CO₂ in a span of ∼20–50 years at...
We have measured the CO₂ concentration of air occluded during the last 40,000 years in the deep Siple Dome A (hereafter Siple Dome) ice core, Antarctica. The general trend of CO₂ concentration from Siple Dome ice follows the temperature inferred from the isotopic composition of the ice and is mostly...