1,719 research outputs found
Microwave-induced nonequilibrium temperature in a suspended carbon nanotube
Antenna-coupled suspended single carbon nanotubes exposed to 108 GHz
microwave radiation are shown to be selectively heated with respect to their
metal contacts. This leads to an increase in the conductance as well as to the
development of a power-dependent DC voltage. The increased conductance stems
from the temperature dependence of tunneling into a one-dimensional electron
system. The DC voltage is interpreted as a thermovoltage, due to the increased
temperature of the electron liquid compared to the equilibrium temperature in
the leads
Uniform non-stoichiometric titanium nitride thin films for improved kinetic inductance detector array
We describe the fabrication of homogeneous sub-stoichiometric titanium
nitride films for microwave kinetic inductance detector (mKID) arrays. Using a
6 inch sputtering target and a homogeneous nitrogen inlet, the variation of the
critical temperature over a 2 inch wafer was reduced to <25 %. Measurements of
a 132-pixel mKID array from these films reveal a sensitivity of 16 kHz/pW in
the 100 GHz band, comparable to the best aluminium mKIDs. We measured a noise
equivalent power of NEP = 3.6e-15 W/Hz^(1/2). Finally, we describe possible
routes to further improve the performance of these TiN mKID arrays.Comment: 7 pages, 4 figures, submitted to Journal of low temperature physics,
Proceedings of LTD-1
Метаморфози терміна "ідентичність" у західній філософській традиції
Стаття присвячена інтерпретації категорії «ідентичність» у європейській філософській традиції від Парменіда
до П. Рікера. Авторка виокремлює головні чотири парадигми її тлумачення: космологічну, теоцентричну,
новоєвропейську та сучасну. У статті також простежується еволюція змістовних значень слова «ідентичність»
у західній та вітчизняній філософії та інших галузях гуманітарного знання.Статья посвящена интерпретации категории «идентичность» в европейской философской традиции от
Парменида до П. Рикера. Автор выделяет четыре главные парадигмы её толкования: космологическую,
теоцентрическую, новоевропейскую и современную. В статье также прослеживается эволюция содержательных
значений слова «идентичность» в западной и отечественной философии и других областях гуманитарного
знания
Anomalous response of superconducting titanium nitride resonators to terahertz radiation
We present an experimental study of KIDs fabricated of atomic layer deposited
TiN films, and characterized at radiation frequencies of ~GHz. The
responsivity to radiation is measured and found to increase with increasing
radiation powers, opposite to what is expected from theory and observed for
hybrid niobium titanium nitride / aluminium (NbTiN/Al) and all-aluminium
(all-Al) KIDs. The noise is found to be independent of the level of the
radiation power. The noise equivalent power (NEP) improves with higher
radiation powers, also opposite to what is observed and well understood for
hybrid NbTiN/Al and all-Al KIDs. We suggest that an inhomogeneous state of
these disordered superconductors should be used to explain these observations
Critical-Current Reduction in Thin Superconducting Wires Due to Current Crowding
We demonstrate experimentally that the critical current in superconducting
NbTiN wires is dependent on their geometrical shape, due to current-crowding
effects. Geometric patterns such as 90 degree corners and sudden expansions of
wire width are shown to result in the reduction of critical currents. The
results are relevant for single-photon detectors as well as parametric
amplifiers
Low loss, high contrast optical waveguides based on CMOS compatible LPCVD processing
A new class of integrated optical waveguide structures is presented, based on low cost CMOS compatible LPCVD processing. This technology allows for medium and high index contrast waveguides with very low channel attenuation. The geometry is basically formed by a rectangular cross-section silicon nitride filled with and encapsulated by silicon dioxide . The birefringence and minimal bend radius of the waveguide is completely controlled by the geometry of the waveguide layer structures. Experiments on typical geometries will be presented, showing excellent characteristics (channel attenuation ≤0.06 dB/cm, IL ≤0.6 dB, PDL ≤0.2 dB, Bg «1 x , bend radius ≤500 μm)
One- and two-photon spectroscopy of a flux qubit coupled to a microscopic defect
We observed the dynamics of a superconducting flux qubit coupled to an
extrinsic quantum system (EQS). The presence of the EQS is revealed by an
anticrossing in the spectroscopy of the qubit. The excitation of a two-photon
transition to the third excited state of the qubit-EQS system allows us to
extract detailed information about the energy level structure and the coupling
of the EQS. We deduce that the EQS is a two-level system, with a transverse
coupling to the qubit. The transition frequency and the coupling of the EQS
changed during experiments, which supports the idea that the EQS is a two-level
system of microscopic origin.Comment: accepted in Physical Review
Misleading graphs in context:Less misleading than expected
Misleading graphs are a source of misinformation that worry many experts. Especially people with a low graph literacy are thought to be persuaded by graphs that misrepresent the underlying data. But we know little about how people interpret misleading graphs and how these graphs influence their opinions. In this study we focus on the effect of truncating the y-axis for a line chart which exaggerates an upgoing trend. In a randomized controlled trial, we showed participants either a normal or a misleading chart, and we did so in two different contexts. After they had seen the graphs, we asked participants their opinion on the trend and to give an estimation of the increase. Finally we measured their graph literacy. Our results show that context is the only significant factor in opinion-forming; the misleading graph and graph literacy had no effect. None of these factors had a significant impact on estimations for the increase. These results show that people might be less susceptible to misleading graphs than we thought and that context has more impact than a misleading y-axis.Science Communication and Societ
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