37 research outputs found
Charge Detection in Phosphorus-doped Silicon Double Quantum Dots
We report charge detection in degenerately phosphorus-doped silicon double
quantum dots (DQD) electrically connected to an electron reservoir. The sensing
device is a single electron transistor (SET) patterned in close proximity to
the DQD. Measurements performed at 4.2K show step-like behaviour and shifts of
the Coulomb Blockade oscillations in the detector's current as the reservoir's
potential is swept. By means of a classical capacitance model, we demonstrate
that the observed features can be used to detect single-electron tunnelling
from, to and within the DQD, as well as to reveal the DQD charge occupancy.Comment: 4 pages, 3 figure
Detection of charge motion in a non-metallic silicon isolated double quantum dot
As semiconductor device dimensions are reduced to the nanometer scale,
effects of high defect density surfaces on the transport properties become
important to the extent that the metallic character that prevails in large and
highly doped structures is lost and the use of quantum dots for charge sensing
becomes complex. Here we have investigated the mechanism behind the detection
of electron motion inside an electrically isolated double quantum dot that is
capacitively coupled to a single electron transistor, both fabricated from
highly phosphorous doped silicon wafers. Despite, the absence of a direct
charge transfer between the detector and the double dot structure, an efficient
detection is obtained. In particular, unusually large Coulomb peak shifts in
gate voltage are observed. Results are explained in terms of charge
rearrangement and the presence of inelastic cotunneling via states at the
periphery of the single electron transistor dot
Emergence of qualia from brain activity or from an interaction of proto-consciousness with the brain: which one is the weirder? Available evidence and a research agenda
This contribution to the science of consciousness aims at comparing how two different theories can
explain the emergence of different qualia experiences, meta-awareness, meta-cognition, the placebo
effect, out-of-body experiences, cognitive therapy and meditation-induced brain changes, etc.
The first theory postulates that qualia experiences derive from specific neural patterns, the second
one, that qualia experiences derive from the interaction of a proto-consciousness with the brain\u2019s
neural activity. From this comparison it will be possible to judge which one seems to better explain
the different qualia experiences and to offer a more promising research agenda