88,551 research outputs found
Two-stage emitter follower is temperature stabilized
Two-stage temperature stabilized circuit using two transistors is described. Increase in temperature causes the base-to-emitter voltage of n-p-n transistor to become less positive whereas the base-to-emitter voltage of p-n-p transistor becomes less negative, so the temperature-induced variation in V sub 1 and V sub 2 cancel out
Sidewall depletion in nano-patterned LAO/STO heterostructures
We report the fabrication of nanostructures from the quasi-two-dimensional
electron gas (q2DEG) formed at the LaAlO/ SrTiO (LAO/STO)
interface. The process uses electron beam lithography in combination with
reactive ion etching. This technique allows to pattern high-quality structures
down to lateral dimensions as small as nm while maintaining the conducting
properties without inducing conductivity in the STO substrate. Temperature
dependent transport properties of patterned Hall bars of various widths show
only a small size dependence of conductivity at low temperature as well as at
room temperature. The deviation can be explained by a narrow lateral depletion
region. All steps of the patterning process are fully industry compatible.Comment: 5 pages, 4 figure
Approximating parabolas as natural bounds of Heisenberg spectra: Reply on the comment of O. Waldmann
O. Waldmann has shown that some spin systems, which fulfill the condition of
a weakly homogeneous coupling matrix, have a spectrum whose minimal or maximal
energies are rather poorly approximated by a quadratic dependence on the total
spin quantum number. We comment on this observation and provide the new
argument that, under certain conditions, the approximating parabolas appear as
natural bounds of the spectrum generated by spin coherent states.Comment: 2 pages, accepted for Europhysics Letter
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