M. Higashiguchi

Direct observation of Tomonaga-Luttinger-liquid state in carbon nanotubes at low temperatures.

The electronic transport properties of conventional three-dimensional metals are successfully described by Fermi-liquid theory. But when the dimensionality of such a system is reduced to one, the Fermi-liquid state becomes unstable to Coulomb interactions, and the conduction electrons should instead behave according to Tomonaga–Luttinger-liquid (TLL) theory. Such a state reveals itself through interaction-dependent anomalous exponents in the correlation functions, density of states and momentum distribution of the electrons. Metallic single-walled carbon nanotubes (SWNTs) are considered to be ideal one-dimensional systems for realizing TLL states. Indeed, the results of transport measurements on metal–SWNT and SWNT–SWNT junctions have been attributed to the effects of tunnelling into or between TLLs, although there remains some ambiguity in these interpretations. Direct observations of the electronic states in SWNTs are therefore needed to resolve these uncertainties. Here we report angle-integrated photoemission measurements of SWNTs. Our results reveal an oscillation in the π-electron density of states owing to one-dimensional van Hove singularities, confirming the one-dimensional nature of the valence band. The spectral function and intensities at the Fermi level both exhibit power-law behaviour (with almost identical exponents) in good agreement with theoretical predictions for the TLL state in SWNTs.

Orbital selectivity of the kink in the dispersion of Sr2RuO4

We present detailed energy dispersions near the Fermi level on the monolayer perovskite ruthenate

Electronic Structure of Charge- and Spin-Controlled Sr1-(x+y)Lax+yTi1- xCrxO3

{\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}

Coherent Heavy Quasiparticles in a CePt5 Surface Alloy

, determined by high-resolution angle-resolved photoemission spectroscopy. An orbital selectivity of the kink in the dispersion of

Rotatable high-resolution ARPES system for tunable linear-polarization geometry

{\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}

Independent control of charge and spin density in Sr1-(x+y)Lax+yTi1-xCrxO3 probed by photoemission spectroscopy

has been found: A kink for the Ru

Independent control of charge and spin density in Sr1-(x+y)Lax+yTi1-xCrxO3Sr1-(x+y)Lax+yTi1-xCrxO3 probed by photoemission spectroscopy

4{d}_{xy}

Independent control of charge and spin density in probed by photoemission spectroscopy

orbital is clearly observed, but not for the Ru

Valence‐Band Photoemission Study of Single‐Wall Carbon Nanotubes

4{d}_{yz}

Photoemission and inverse photoemission study of the electronic structure of C60 fullerenes encapsulated in single-walled carbon nanotubes

and