The quantized anomalous Hall effect (QAHE) have been theoretically predicted and experimentally confirmed in magnetic topological insulators (TI), but dissipative channels resulted by small-size band gap and weak ferromagnetism make QAHE be measured only at extremely low temperature (<0.1 K). Through density functional theory calculations, we systemically study of the magnetic properties and electronic structures of Mn doped Bi2Se3 with in-plane and out-of-plane strains. It is found that out-of-plane tensile strain not only improve ferromagnetism, but also enlarge Dirac-mass gap (up to 65.6 meV under 6% strain, which is higher than the thermal motion energy at room temperature ~26 meV) in the Mn doped Bi2Se3. Furthermore, the underlying mechanisms of these tunable properties are also discussed. This work provides a new route to realize high-temperature QAHE and paves the way towards novel quantum electronic device applications.

No abstract

Substrate coupling noise is a key problem in today's large mixed-signal systems. This noise is caused by the coupling of digital part and can propagate to analog circuits through the common substrate. The estimating and accurate modeling of noise coupling effects is a major challenge for designers. In this paper, method of 3D distributed resistive-capacitive is used to modeling the substrate, meanwhile power/ground network models are built. Also the noise injection is got by the ring oscillator which can inject noise more real. Finally, the above models are applied in a high-speed Flash ADC and then quantifying the impact of substrate coupling noise on the performance of the circuit.

Quantum anomalous Hall effect (QAHE) is a fundamental quantum transport phenomenon in condensed matter physics. Until now, the only experimental realization of the QAHE has been observed for Cr/V-doped (Bi,Sb)2Te3 but at extremely low observational temperature, thereby limiting its potential application in dissipationless quantum electronics. Employing first-principles calculations, we study the electronic structures of graphene codoped with 5d transition metal and boron (B) atoms based on a compensated n-p codoping scheme. Our findings are as follows. 1) The electrostatic attraction between the n-and p-type dopants effectively enhances the adsorption of metal adatoms and suppresses their undesirable clustering. 2) Hf-B and Os-B codoped graphene systems can establish long-range ferromagnetic order and open nontrivial band gaps because of the spin-orbit coupling with the non-vanishing Berry curvatures to host the QAHE. 3) The calculated Rashba splitting energy in Re-B and Pt-B codoped graphene systems can reach up to 158 and 85 meV, respectively, which is several orders of magnitude higher than the reported intrinsic spinorbit coupling strength.

No abstract