5,448 research outputs found
Topological phase in topological Kondo insulator: topological insulator, Haldane-like phase and Kondo breakdown
We have simulated a half-filled -wave periodic Anderson model with
numerically exact projector quantum Monte Carlo technique, and the system is
indeed located in the Haldane-like state as detected in previous works on the
-wave Kondo lattice model, though the soluble non-interacting limit
corresponds to the conventional topological insulator. The
site-resolved magnetization in an open boundary system and strange correlator
for the periodic boundary have been used to identify the mentioned topological
states. Interestingly, the edge magnetization in the Haldane-like state is not
saturated to unit magnetic moment due to the intrinsic charge fluctuation in
our periodic Anderson-like model, which is beyond the description of the Kondo
lattice-like model in existing literature. The finding here underlies the
correlation driven topological state in this prototypical interacting
topological state of matter and naive use of non-interacting picture should be
taken care. Moreover, no trace of the surface Kondo breakdown at zero
temperature is observed and it is suspected that frustration-like interaction
may be crucial in inducing such radical destruction of Kondo screening. The
findings here may be relevant to our understanding of interacting topological
materials like topological Kondo insulator candidate SmB.Comment: 11 pages, 9 figures, accepted by EPJ
A Differential Approach for Gaze Estimation
Non-invasive gaze estimation methods usually regress gaze directions directly
from a single face or eye image. However, due to important variabilities in eye
shapes and inner eye structures amongst individuals, universal models obtain
limited accuracies and their output usually exhibit high variance as well as
biases which are subject dependent. Therefore, increasing accuracy is usually
done through calibration, allowing gaze predictions for a subject to be mapped
to his/her actual gaze. In this paper, we introduce a novel image differential
method for gaze estimation. We propose to directly train a differential
convolutional neural network to predict the gaze differences between two eye
input images of the same subject. Then, given a set of subject specific
calibration images, we can use the inferred differences to predict the gaze
direction of a novel eye sample. The assumption is that by allowing the
comparison between two eye images, annoyance factors (alignment, eyelid
closing, illumination perturbations) which usually plague single image
prediction methods can be much reduced, allowing better prediction altogether.
Experiments on 3 public datasets validate our approach which constantly
outperforms state-of-the-art methods even when using only one calibration
sample or when the latter methods are followed by subject specific gaze
adaptation.Comment: Extension to our paper A differential approach for gaze estimation
with calibration (BMVC 2018) Submitted to PAMI on Aug. 7th, 2018 Accepted by
PAMI short on Dec. 2019, in IEEE Transactions on Pattern Analysis and Machine
Intelligenc
- …