900 research outputs found
Bosonization of quantum sine-Gordon field with a boundary
Boundary operators and boundary ground states in sine-Gordon model with a
fixed boundary condition are studied using bosonization and q-deformed
oscillators.We also obtain the form-factors of this model.Comment: Latex 25page
Securing Cyber-Physical Social Interactions on Wrist-worn Devices
Since ancient Greece, handshaking has been commonly practiced between two people as a friendly gesture to express trust and respect, or form a mutual agreement. In this article, we show that such physical contact can be used to bootstrap secure cyber contact between the smart devices worn by users. The key observation is that during handshaking, although belonged to two different users, the two hands involved in the shaking events are often rigidly connected, and therefore exhibit very similar motion patterns. We propose a novel key generation system, which harvests motion data during user handshaking from the wrist-worn smart devices such as smartwatches or fitness bands, and exploits the matching motion patterns to generate symmetric keys on both parties. The generated keys can be then used to establish a secure communication channel for exchanging data between devices. This provides a much more natural and user-friendly alternative for many applications, e.g., exchanging/sharing contact details, friending on social networks, or even making payments, since it doesn’t involve extra bespoke hardware, nor require the users to perform pre-defined gestures. We implement the proposed key generation system on off-the-shelf smartwatches, and extensive evaluation shows that it can reliably generate 128-bit symmetric keys just after around 1s of handshaking (with success rate >99%), and is resilient to different types of attacks including impersonate mimicking attacks, impersonate passive attacks, or eavesdropping attacks. Specifically, for real-time impersonate mimicking attacks, in our experiments, the Equal Error Rate (EER) is only 1.6% on average. We also show that the proposed key generation system can be extremely lightweight and is able to run in-situ on the resource-constrained smartwatches without incurring excessive resource consumption
Theory of anomalous Hall effect in transition-metal pentatelluride and
The anomalous Hall effect has considerable impact on the progress of
condensed matter physics and occurs in systems with time-reversal symmetry
breaking. Here we theoretically investigate the anomalous Hall effect in
nonmagnetic transition-metal pentatelluride and
. In the presence of Zeeman splitting and Dirac mass, there
is an intrinsic anomalous Hall conductivity induced by the Berry curvature in
the semiclassical treatment. In a finite magnetic field, the anomalous Hall
conductivity rapidly decays to zero for constant spin-splitting and vanishes
for the magnetic-field-dependent Zeeman energy. A semiclassical formula is
derived to depict the magnetic field dependence of the Hall conductivity, which
is beneficial for experimental data analysis. Lastly, when the chemical
potential is fixed in the magnetic field, a Hall conductivity plateau arises,
which may account for the observed anomalous Hall effect in experiments.Comment: 11 pages, 6 figures, reference information is update
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