249 citations · 1.1k across the 47 of their papers we have counts for
47 papers
Narrow-Sense Type-III Dirac Cones and Additional Flat Lines on a Honeycomb Lattice with Anisotropic Next-Nearest-Neighbor Hoppings
Keita Kishigi, Yasumasa Hasegawa
Critically tilted Dirac cones have attracted considerable attention because of their unconventional electronic properties in two-dimensional massless Dirac-fermion systems. Among t…
Crossover in Electronic Specific Heat near Narrow-Sense Type-III Dirac Cones
Keita Kishigi, Yasumasa Hasegawa
Two-dimensional massless Dirac fermions exhibit Dirac cones, which are classified into three types: type-I, type-II, and type-III. In both type-I and type-II cones, the energy disp…
Observable precursor of topological phase transition: temperature-dependent electronic specific heat in two-dimensional Dirac fermions
Keita Kishigi, Keita Tsukidashi, Yasumasa Hasegawa
Dirac points in two-dimensional massless Dirac fermions are topologically protected. Although single Dirac point cannot disappear solely, a pair of two Dirac points annihilates aft…
De Haas-van Alphen oscillations near the Lifshitz transition from two electron pockets to one electron pocket in the two-dimensional Dirac fermion systems
Keita Kishigi, Yasumasa Hasegawa
We theoretically study the de Haas-van Alphen (dHvA) oscillations in the system with changing the topology of the Fermi surface (the Lifshitz transition) by electron dopings. We em…
Superconductivity near the saddle point in the two-dimensional Rashba system Si(111)--(Tl,Pb)
T. Machida, Y. Yoshimura, T. Nakamura +7
Two-dimensional Rashba superconductor Si(111)--(Tl,Pb) is a candidate platform of mixed spin-singlet and -triplet superconductivity. A recent scanning tunne…
Enhancements of the 3/2 and 5/2 frequencies of de Haas-van Alphen oscillations near the Lifshitz transition in the two-dimensional compensated metal with overtilted Dirac cones
Keita Kishigi, Yasumasa Hasegawa
We study the de Haas-van Alphen (dHvA) oscillations in the two-dimensional compensated metal with overtilted Dirac cones near the Lifshitz transition. We employ the tight-binding m…